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(x-18)/7=6 2017-08-08
From David:
Answered by Penny Nom.
13 - 3x = x times the square root of 5 2017-03-29
From Kevin:
A student I am tutoring was sent this question from his teacher.

Solve for x: 13 - 3x = x times the square root of 5

Answered by Penny Nom.
2^x= -2x - 11 2016-11-27
From Kathy:
I don't know how to start this problem:
2^x= -2x - 11

Answered by Penny Nom.
An equation with fractions 2016-11-09
From Tina:
How do you solve x+1/3=x+2/5. X+1 divided by 3= x+2 divided by 5. What's x=
Answered by Penny Nom.
A word problem 2015-09-17
From Suszanne:
Multiplying a number by x yields the same result as dividing the number by 0.125. What is the value of x?
Answered by Penny Nom.
Manipulating an equation 2014-04-12
From Paul:
S=4wl+2wh and solve for h
Answered by Penny Nom.
x^3+(1/x^3)=18√3 2014-02-23
From Asiv:
if x^3+(1/x^3)=18√3; then what is the value of x?
Answered by Penny Nom.
When would one flip the inequality sign? 2014-01-09
From Natasha:
Would one flip the inequality symbol in this equation: (explain why) (-9a)/(-9) > 81
And please explain in what circumstances one would flip the inequality sign

Answered by Penny Nom.
Solve 0=-2(x-5)^2+4 2013-11-17
From Leila:
How do you find the solution to 0=-2(x-5)^2+4
Answered by Penny Nom.
2^x . 5^3 = x^4 2013-09-05
From Zuhdina:
Hi, I got a question, 2^x . 5^3 = x^4 I want to know the value of x without using calculator, I've already done some questions in logarithm and I always stuck in the same model equation-I think if someone shows me the way, I can do the other 'stuck equations'
Answered by Penny Nom.
Solve x = ln(x) 2013-07-19
From Udayan:
Sir/Madam, How to find the solutions of the equation, x = ln(x)
Answered by Penny Nom.
4=(1+.08)^x 2013-06-15
From Samantha:
I can't seem to understand how to solve for x when it is in power form, here is the equation:


Answered by Penny Nom.
7x-1/4-1/3[2x -1-x/2]=19/3 2013-02-03
From M:
7x-1/4-1/3[2x -1-x/2]=19/3
Answered by Penny Nom.
Sinx=logx+x^2 2012-11-28
From yasmin:
Answered by Harley Weston.
Solving for a/b 2012-10-21
From Jenny:
If a + 3b is equal to 175% of 6b, what is the value of a/b?
Answered by Penny Nom.
Solve 8t-r=12t for t 2012-09-29
From Monejah:
I need help solving 8t-r=12t for t
Answered by Penny Nom.
(2y+1)/3=(1y-1)/2 2012-09-06
From jenna:
Answered by Penny Nom.
2x+underroot2=3x-4-3underroot2 2012-07-09
From Eshraj:
Answered by Penny Nom.
Two equations involving fractions 2012-06-12
From Fatima:
Hi ,teacher gave two question to my daughter as follows
Solve 2/x+3=(1/xx-9)-(1/x-3)and
Solve (4/x-2)-(x/x+2)=16/xx-4

Please help me
Thanks & regards fatima

Answered by Penny Nom.
Solve for x 2012-05-12
From Desiree:
3x -5^2=8
Answered by Penny Nom.
-8(3x+4)+6x=4(x-8 )+4x 2012-01-18
From bianca:
-8(3x+4)+6x=4(x-8 )+4x
Answered by Penny Nom.
Solve for theta if 8cos^2 theta-3=1 2011-12-02
From Katherine:
Hi, I have just learned to solve trigonometric problems for theta and have one specific question in order to find the solutions to my homework. I will use one example for this question. If I have 8cos^2 theta-3=1 I first divide by 8 and get cos^2theta=3/8 then I have cos theta= plus or minus the square root of 3/8 Then I assume that I plug in inverse cos (the square root of 3/8) to my calculator. How do I find the four solutions (we are typically supposed to find four, I believe?) Can you help me with finding the solution to this problem? Thank you!
Answered by Penny Nom.
A right angled triangle 2011-04-22
From jeremy:
Solve the right triangle with the given sides and angles. a=3.0 cm and b=1.6 cm
Answered by Penny Nom.
6(M-1/9)=55/12 2011-03-15
From Colleen:
Answered by Penny Nom.
Rearrange for x 2011-02-06
From sue:
(x+7)/3 = (3xy+2x)/4 rearrange for x
Answered by Penny Nom.
An algebra problem with fractions 2010-10-16
From Morgan:
Hi my math teacher has given us this question for our grade nine math class and I always get confused about multiple x algebra, could you help me?

6x+4        3x+2
------   =  ------
  3               5

I have no problems until it comes to combining integers, or x's

Answered by Penny Nom.
2x − 1 ( 1 − 2x) = 1 ( 2x − 2x) 2010-10-08
From MC:
Solve 2x − 1 ( 1 − 2x) = 1 ( 2x − 2x) for x

I am befuddled! Thank you for any explanation you can give that show me the steps. I know the order in which I should tackle it, but am so confused regarding how to assume x. Thank you!

Answered by Penny Nom.
A linear equation with the variable on both sides 2010-01-16
From dog:
Answered by Penny Nom.
4x +3/4 = 1/4 2009-12-12
From Lynda:
4x +3/4 = 1/4

I know the answer is -1/8 but I don't know how to show the process of getting the answer

Answered by Penny Nom.
at+b=ar-c, solve for a 2009-09-16
From kimberly:
at+b=ar-c, solve for a
Answered by Penny Nom.
10x-8 /3 =6x+24 /5 2009-09-16
From Heidi:
10x-8 /3 =6x+24 /5.....I know the answer is 7/2 but how do I get there?
Answered by Penny Nom.
Sequence problem 2009-08-18
From James:
I have the equation: tn = (n)(n+1)/2 Which gives the sequence: 1, 3, 6, 10, 15 etc. However, I'd like to be able to solve for n. So that a t of 6 would give me the answer of 3, and t of 10 would give me the answer 4 etc.
Answered by Stephen La Rocque and Victoria West.
Solve for s 2009-08-12
From Michelle:
My daughter and I are having trouble with this problem...All it says i solve thr formula for the indicated variable.
Height of an Equilateral Triangle.

Solve for s:

H= square root of 3/2 * S

Answered by Penny Nom.
Solve 18(C-3)=162 for C 2009-05-29
From Alicia:

adult student returning to school after 20 years and then never had it in school. Just doesn't click yet

Answered by Penny Nom.
Negative nine minus 7x = negative 5 2009-04-23
From gigi:
what is negative nine minus 7x = negative 5
Answered by Robert Dawson.
Make x the subject in this equation 2009-04-16
From victoria:
i need help trying to make x the subject in this equation:
7y + 2x = 15
i'm really stuck so any help will be good,


Answered by Penny Nom.
A five game average of 148 2009-04-01
From Shelly:
(128 + 145 + 139 + 157 + x) divided by 5 = 148 matches the situation stated below:

A person bowled four games and scored 128, 145, 139, and 157. Find x, the score the person would need to have in the fifth game to average 148 for all five games.

How do I solve this and how am I supposed to add x like it says in the equation?

Answered by Penny Nom.
x^2/5 - 4/5 = -3/5x 2009-03-25
From Lorrie:
x^2/5 - 4/5 = -3/5x
Answered by Penny Nom.
Solving an equation for b 2009-03-13
From ernest:
If 2b=96+b+96+1/2b solve for b?
Answered by Penny Nom.
Solve for x 2009-01-16
From maritza:
Answered by Penny Nom.
Solving an equation for D 2008-12-18
From Darrin:
In his finance class, my son is being asked to take the following equation and solve for "D":

1 / [1 - (1 + D/12)^T] = (1 / D) * [((12*B) / (P*T)) + Y + ((12N * Z) / (360T))] - [(12Z) / (360T)] * F

Answered by Robert Dawson.
Solve for x 2008-12-16
From Melissa:
I have a test tomorrow and I'm hoping you can help me before then. I can never seem to solve the "RESOLVE X" problems, or in french resous pour x/
They look like this. 3x+2\6=2x-5\3. I only understand NOTHING from that. Another equation is 2(x+1)=3(x+2).

Answered by Robert Dawson and Penny Nom.
Solve 3x +5= 4x-10 2008-11-22
From Nikko:
HELP please how do I solve these type of questions? 3x +5= 4x-10 or 4x +10= 6x-8
Answered by Penny Nom.
Solve the equation 2x + y = 6 for y. 2008-11-07
From fatiuma:
Solve the equation 2x + y = 6 for y.
Answered by Penny Nom.
Equations with the variable in the exponent 2008-10-28
From fari:
Solve for x

5 * 4^x-3=40

Answered by Penny Nom.
A linear equation with fractions 2008-10-07
From Christopher:
Answered by Penny Nom.
(5x - 4) / 6 = -9 2008-09-09
From Conor:
Solve to find x:

(5x - 4) / 6 = -9

Answered by Penny Nom.
1/3(2x-1)=1 2008-09-07
From Jen:
Answered by Penny Nom.
v-4(4-v) = -2(2v-1) 2008-08-29
From c:
Please explain all the steps to solving this

v-4(4-v) = -2(2v-1)

Answered by Penny Nom.
Solve for y in terms of x 2008-08-10
From Rosie:
Solve equation for y


Answered by Penny Nom.
Solving for Two Variables 2008-07-24
From Mary:
can you help, 2/35= 1/x +1/y ; x
Answered by Janice Cotcher, Victoria West and Harley Weston.
x=(-14x+16)/x-8 2008-06-11
From Kory:
Solve the equation.

Answered by Penny Nom.
x/4 = 3 1/2 2008-05-30
From Kelsey:
How do you solve for "X" in the problem below?

--- = 3 1/2


Answered by Victoria West.
15 + 0.10n = 0.25n, solve for n 2008-04-24
From monica:
15 + 0.10n = 0.25n

Solve for n.

Answered by Penny Nom.
(32-2 x 5) divided by 2 + 8 2007-11-28
From Kim:

(32-2 x 5) divided by 2 + 8

Answered by Leeanne Boehm.
How to solve related rates problems 2007-10-27
From David:
Can you plz explain how and where you come up with an equation to solve this?
Find the rate of change of the distance between the origin and a moving point on the graph of y = sin x if dx/dt = 2 centimeters per second.

Answered by Stephen La Rocque.
sin 43= y/20 2007-10-21
From stefany:
if sin 43= y/20, what is the value of y to the nearest tenth?
Answered by Penny Nom.
5x + 9 = 3x + 7 2007-10-16
From kristina:
hi im kristina and i cannot figure out how 2 do these multi-step equations

5x + 9 = 3x + 7 i can on getting the wrong answer according 2 the book

Answered by Penny Nom.
Four triangles in a square 2007-10-15
From Kristina:
A square with side lengths of 6 cm is divided into 3 right triangles and a larger isosceles triangle. If the three right triangles have equal area, find the exact area of the isosceles triangle.
Answered by Stephen La Rocque.
Solving four simultaneous equations (system of four linear equations) 2007-10-07
From Johan:
I need some help in solving this question
x + 2y - 3z + 4w = 12
2x + 2y - 2z + 3w = 10
0 + y + z + 0 = -1
x - y + z - 2w = -4

Answered by Stephen La Rocque.
Solve for K 2007-10-05
From Ben:
Solve the formula for K C=30d+0.10k
Answered by Stephen La Rocque.
1/2+X=5/8 2007-09-24
From Tasha:
What is the sum of X in the problem below and explain your answer please?


Answered by Chris Langdon.
13 = x/20 2007-09-06
From Melissa:
can u please help me with this question?
13 = x/20

Answered by Penny Nom.
z+81 = 9z-7 2007-08-24
From Erin:
Question from erin, a student:


Answered by Stephen la Rocque.
More on a percentage question 2007-08-23
From Dee:
In a previous question, you answered:

"What percentage of $34.51 is $10.71?

I translate this English statement into a mathematical statement (equation) using the following

"what" is the unknown, call it x
"percent" is per-one-hundred, that is over 100
"of" is multiplication
"is" is the verb, which in an equation is the equal sign
Thus the English statement above becomes

x/100 $34.51 = $10.71

Solving for x yields

x = 31.03

Hence the gross profit is 31% of your selling price."

How did you solve for 'x'

Answered by Penny Nom.
(2x + 3y)^2 = 0 2007-06-21
From Jon:
how do i solve for x and y if (2x+3y)²=0?
Answered by Stephen La Rocque.
Algebra : 9x + 7 = 5x - 3 2007-06-15
From Allen:
I am having a problem solving for x. The problem is: 9x + 7 = 5x - 3
Answered by Stephen La Rocque.
Algebra - find the number 2007-06-04
From Fabiola:
When 4 times a number is increased by 40, the answer is the same as when100 is decreased by a number. Find the number
Answered by Stephen La Rocque.
Solve for I 2007-05-23
From Mark:
A=4.9(B)*C^(.00925(D-.542))* E^(-.015(D))*E^(-.013(F))* (G/B)^(-.00825(D-.225))* H^-.877*(I/B)^.511*(J/B)^.319
Answered by Stephen La Rocque.
Algebra (Solve for B) 2007-05-23
From Mark:
A = .250 * (B^2*SIN(C)) / (D*COS^2(E)). I need to solve for B.
Answered by Stephen La Rocque.
Base seven 2007-05-19
From Dan:
A number X is converted to base 7 and becomes a four digit number. Its leftmost digit is removed and written again as the rightmost digit. The number thus obtained is twice X. Find the decimal representations of all such numbers X.
Answered by Penny Nom.
Find the real solutions in this trig equation 2007-05-09
From tony:
list all real solutions of the equation that are in the interval [0,2π)
2cos(x) + tan(x) = sec(x)

Answered by Penny Nom and Stephen La Rocque.
What is 2x + 1? 2007-04-30
From Cynthia:
Hi, How do I solve this problem? If -1/3x + 7= 16, what is the value of 2x+1 Thanks, Cynthia
Answered by Stephen La Rocque.
.07 = (1 + x)/(1+.12) - 1 2007-04-17
From Kathy:
How would you solve

.07 = (1 + x)/(1+.12) - 1

Answered by Stephen La Rocque.
Solve for x and y 2007-03-27
From anthony:
solve y=4x and x+y=5
Answered by Sara Ulmer.
Solve for c 2007-02-26
From Steffane:
A over m = b over c sorry I can't put them over each other
Answered by Penny Nom.
Algebra 2007-02-13
From B.Wilson:
The teacher has asked to solve the following, but I have never seen this before: 6x/2 = 4x/5
Answered by Haley Ess.
11^n +22^n = 55^n 2007-01-29
From Ankit:
11^n +22^n = 55^n

find the value of n?

Answered by Penny Nom.
(3x+5) / 2 = (5x+3) / (3)+ 2 2007-01-22
From Jaclyn:
(3x+5) / 2 = (5x+3) / (3)+ 2
Answered by Penny Nom.
x divided by 8+2= 3x divided by 4-3. 2007-01-18
From Fabiola:
x divided by 8+2= 3x divided by 4-3.
need to solve for x

Answered by Penny Nom.
solve; 2006-11-28
From Monique:
solve; f(f(x)) = 2x + 4 ; if f(x) = 1
Answered by Penny Nom.
(x - 5)/3 - 3/2 = (4x + 7)/6 2006-11-23
From Terri:
I have never had algebra before and I am finding it difficult.Can you please help me work this problem out?

(x - 5)/3 - 3/2 = (4x + 7)/6

Answered by Penny Nom.
4/7x+3=15 2006-11-04
From Ashley:
Solve 4/7x+3=15
Answered by Penny Nom.
Balancing equations 2006-10-26
From Della:

With the following equations, how do you know whether you need to apply the multiplication or division rule of equality?

75% t = 18

120% w = 72

Answered by Penny Nom.
How do you solve for variables in the denominator? 2006-10-15
From Donna:
How do you solve for variables in the denominator?

178 = 17/R
Answered by Stephen La Rocque.

Solving a linear equation 2006-10-12
From Eriona:
6p-5=17. I have to solve the equation.
Answered by Penny Nom.
30+7(x-1)=3(2x+7) 2006-09-29
From Art:

I know with the distributive law I multiply 7 by x and 7 by -1 and the same thing to the right, only 3 by 2 and 7 than I am lost?
Answered by Penny Nom.

X^1/3-X^1/9=60 2006-09-26
From Harini:
I need the answer for

The value of X in X^1/3-X^1/9=60.
Answered by Penny Nom.

If 5x + 4y = 6 then x + y = ? 2006-08-18
From Vijai:
If 5x+4y=6 then x+y=?
Answered by Stephen La Rocque and Penny Nom.
x+ 6 / 3 = x+ 6 / x 2006-08-01
From Lynne:
x+ 6 / 3 = x+ 6 / x
How do I solve this equation?

Answered by Penny Nom.
[(400/n)-5](n+ 4)=400 2006-07-02
From Maria and George:

Can somebody solve for n in the following equation please?

[(400/n)-5](n+ 4)=400

Answered by Penny Nom.
2x+5y=3 And -x+3y=-7 2006-04-03
From Lloyd:
simplify 2x+5y=3 And -x+3y=-7
Answered by Penny Nom.
3z-5+2z=25-5z 2005-10-02
From Davis:
Answered by Penny Nom.
U'(X) - U(X) = 0; U(0) = 2 2005-09-23
From David:
Out of interest could you please answer the following questions?

U'(X) - U(X) = 0; U(0) = 2


U''(X) - U'(X) = 0; U'(0) = U(0) = 2

Answered by Harley Weston.
How do you solve 3x^2 + x - 2 = 0 2005-09-15
From Lizzy:
How do you solve 3x2 + x - 2 = 0
Answered by Penny Nom.
y = log(x) + x. Solve for x. 2005-08-26
From Alain:

I have the following equation:

y = ln(x) + x

How do I solve for x?

Answered by Penny Nom.
3A/4 +1=(2A-1)/3 2005-08-21
From Rachael:

I'm doing a practice test question and the answer I keep turning out is different from the answer on the answer sheet. I think I might be forgetting a step. The problem is:

3A/4 +1=(2A-1)/3

The answer is -16. If anyone could explain the steps to me to getting the answer I would be grateful. Whenever I do it I get something completely different.

Answered by Penny Nom.
Solve for x 2005-07-20
From Ed:
(x-1)/3 - 1 = (x + 2)/2
Answered by Penny.
y = x+2 and y = 2x - 1 2005-05-03
From Kimberley:
Question: y=x+2 y=2x-1
Answered by Penny Nom.
Solve for x 2005-02-02
From Christie:
Solve for x

.387 = (.40 - .265x)/(sqrt(1-x2))

Answered by Penny Nom.
1/x + 1/y = 2/31 2004-12-01
From matt:
I have this problem which I think is a bit more tricky than usual. x and y are positive integers.

1/x + 1/y = 2/31

Answered by Claude Tardif.
e = ln(b/a) solve for a 2004-12-01
From Daniel:
I am trying to make "a" the subject of this equation "e = ln(b/a)" but am not sure if i'm doing it right. Any help would be appriciated,
Answered by Claude Tardif.
Solve for a and t 2004-10-23
From Justin:
How do I solve for "a" and "t" in the equations:

1000t= -4000 + 2000t + (1/2)at^2
1000=2000 + at

Answered by Penny Nom.
Solve for z 2004-08-30
From Ana:
Solve for z when 4x + 10yz = 0

solve for z if y2 + 3yz - 8z - 4x = 0?

Do I have to solve all of the variables in order to get z?

Answered by Penny Nom.
x^2 = x + 2 2004-07-26
From A parent:
x2 = x+2

My daughter came home with this equation today and although I know the answer is x=2, i have no way of proving it by showing any working out.

Answered by Penny Nom.
Solving some quadratic equations 2004-07-15
From A student:
Could you please solve the following for x


Answered by Penny Nom.
12(1.221)^t = t + 3 2004-07-14
From Jay:
This problem has me stumped since i cannot separate the t and the 3. Here it is:

12(1.221)t = t + 3

It's on a logarithm worksheet, but how do i figure it out?!

Answered by Harley Weston.
x = 2^x 2004-07-12
From A student:
If the graphs of y=x and y=2x are drawn on the same set of axes, they will intersect when x is equal to what?

(4)They won't intersect.

I know the answer is number 4 by graphing which is permitted; however, I would like to know if there is any algebraic way to do this type of problem.If yes, please show me how.Thanks.

Answered by Penny Nom.
Solving an equation 2004-06-14
From Anthony:
I was hoping that you could help me with this problem. I believe that this is a high school level problem but as an adult who has forgotten the "rules", I am stuck.

the equation is this: x=t2/(t1-t2)

we know that x=5.73

we must solve for t2

Answered by Penny Nom.
x^2/3 - 7 x^1/3 + 12 = 0 2004-04-05
From Jackie:
I am having trouble solving this question for x:

1.) x^2/3 - 7 x^1/3 + 12 = 0

Answered by Penny Nom.
The intersection of two graphs 2004-03-31
From Benjanim:
How do I find the points of intersection of the two functions:

1) y = 2 - (e^-x)
2) y = 1 + (x^2)

I know that I have to set them equal to each other, but I can't solve for x. Please help :-)

Answered by Penny Nom.
z^2 = 3 - 4i 2004-03-26
From John:
Solve: Z^2 = 3 - 4i
Answered by Harley Weston.
Solving an equation 2004-01-03
From A student:
the question is to solve and check equations and the question is
2n + 3n + 7 = -41

Answered by Penny Nom.
Diamonds and Pearls 2003-12-11
From Lauren:
A crown holds a total of 3080 jewels.
It is made up of diamonds and pearls.
There are 10 times as many diamonds as there are pearls.
How many pearls are there?

Answered by Penny Nom.
4(r-2) = r(2+8) 2003-11-20
From Angela:
I not going to give you the problem that I have, but a problem like it. 4(r-2) = r(2+8) I get mix up trying to solve a problem like this could you help me. So that I will be able to handle the ones on my homework.
Answered by Penny Nom.
Solve for Q 2003-11-03
From Anwaar:

The problem is:

QT - X
________ + H = HT

Answered by Peny Nom.
Solve for x 2003-10-27
From Lonnie:
i need help with solving equations and formulas such as -3x+b=6x, for x. I do not understand how you find x.
Answered by Penny Nom.
Substitution method 2003-09-14
From John:

Hello, my name is john and while I was finishing up my work I stumbled into these problems. a/4-b=-1

Thanks a lot. I really need some help :)

Answered by Penny Nom.
Two equations 2003-08-21
From Jennifer:

The following problems have me stuck and any help would be greatly appreciated seeing my text book is doing me no favours:

32a+1 - 283a + 9=0
52m - 5m=20

Answered by Penny Nom.
|x+3| = -15x 2003-07-19
From Nathan:
Without the use of trial and error, is there a way of solving for x where |x + 3| = -15x? I know that x = -0.1875, but how do I find whether x + 3 is positive or not if I did not have this information (In other words, how would I solve whether the x-value was -3 or less, or if it was more than -3)?
Answered by Claude Tardif and Penny Nom.
Solve x = y^z for z 2003-06-28
From Nathan:
If x = y^z is there a way to solve for z, if x and y are given, without guessing or already knowing the answer?

ie: 64 = 2^z
6 is the obvious value for z. Is there a way I could solve for this variable using a formula, which would also apply when more complex values were substituted for x and y?

Answered by Penny Nom.
R= 5.3lnx + x. 2003-05-11
From A student:
Reaction R to a dose x is given by: R= 5.3lnx + x. For a certain drug, R must not exceed 21. Show that a dose between 8 and 12 units satisfies this requirement & find, correct to 5 decimal places, the greates value of x which satisfies this condition?
Answered by Harley Weston.
12*nC2 = n! 2003-03-30
From A tutor:
Solve for "N"


Answered by Walter Whiteley.
(n+17)(n+7) = 0 2003-03-05
From Janea:

What is the answer to 1. (n+17)(n+7)=0

What is the answer to:2. (y-15)(y-100)=0

Answered by Penny Nom.
Two equations in two unknowns 2003-02-06
From Patrick:
What are all ordered pairs of real numbers (x, y) for which: yx2 - 7x + 12 = 1 and x + y = 6?
Answered by Penny Nom.
The intersection of conics 2002-12-19
From Glenda:
We are studying systems of equations where two conic sections are the two equations that we are solving simultaneously. We were studying the number of solutions that are possible if you have an ellipse and a parabola. We all agree that there can be none, one, two, three or four solutions. The question that the students had for me was whether or not a portion of an ellipse and a parabola can overlap and thereby allow an infinite number of solutions. What should I tell them?
Answered by Chris Fisher and Harley Weston.
Find a, b and c 2002-12-10
From Sameer:


Answered by Penny Nom.
Quadratic equations 2002-12-10
From Katie:
just bugging the hell outta me and I cannot figure it out for the life of me.

1)x-2x-1 =0
Find both roots. You must simplify both of your roots. This equation requires the use of the Quadratic Formula. I have tried everything for this and I am still either getting the wrong answers, and end up getting really frustrated. If you could find the answers and tell me how you did it I would greatly appreciate it! Then the second problem is

2) The square of a certain negative number is equal to 70 decreased by 3 times the number. Find the answer! On this one I set it up but still came out with the wrong answer. So if you could help me on this one I would greatly appreciate it!

Answered by Penny Nom.
Algebra 2002-11-13
From Carol:
I am a confused parent trying to help my dau hgter solve some math problems and I need help.


Answered by Penny Nom.
x intercepts 2002-11-10
From Laura:
Find the x intercepts for the graph of the equation.

x 2 - x - 12 = 0

Answered by Penny Nom.
(93+n)+158=93+(28+158) 2002-11-10
From Parents:
Answered by Penny Nom.
G = 3H - 5 2002-11-07
From Kash:
G=3H-5, for H solve for the given variable
Answered by Penny Nom.
Determining a parabola 2002-11-06
From Shelley:
let (0,3) and (1,9)and (-1,1) be given points in a parablola. Determine a b and c
Answered by Penny Nom.
How many trees were planted in March? 2002-10-20
From Allison:
The number of trees planted by the Alpine Nursery in April was 3 more than twice the number of trees planted in March. If 71 trees were planted in april, write and solve an equation to find how many trees were planted in March.
Answered by Penny Nom.
Solving an equation 2002-09-22
From Emanuel:
how do u solve these problems?:

30/x=7+ 18/2x

3m+1/4 = 2- 3-2m/3

Answered by Penny Nom.
Express 5120 as a sum of consecutive numbers 2002-08-25
From Todd:
Express 5120 as a sum of more than 1 consecutive number.
Answered by Leeanne Boehm.
Two equations 2002-07-26
From Derek:
1. 3x + 2y = 4
2. -7x + 2y = 24

finding x and y.

Answered by Penny Nom.
Some inequalities 2002-07-25
From A student:

1)-5 <= -3X+1 < 1

2)4X-2 < 6 OR X+2 > 9

Answered by Penny Nom.
25m = 100 2002-04-22
From Megan:
If 25m = 100, Then m equals what number?
Answered by Penny Nom.
Solve for x 2002-04-20
From A student:
solve for x.
  c-x      2x+b ----- = --------   a        c 

Answered by Peny Nom.
An augmented matrix 2002-04-20
From A student:
Hi my math teacher asked us to solve an augmented matrix. I am in twelfth grade and need help. The book we are working on is college algebra. Here it is


Answered by Penny Nom.
Solving for x 2002-04-19
From Susan:
I'm having a little trouble solving these equations for x. I can't seem to separate x fully from the other numbers. Please help! Here are the problems:

(2x-1)/(x-2)(x 2+3) = 0 and

Answered by Penny Nom.

Two algebra problems 2002-04-14
From Ashley:
Question 1: For all values of a, let < a > be defined as < a > = 4a - 4 . Which of the following equals < 6 > - < 5 >? A: < 2 >
B: < 3 >
C: < 4 >
D: < 5 >
E: < 6 >

Question 2: If 5n + p = 3 and 2m - 10n = 2, what is the value of m + p?

Answered by Penny Nom.
3/4n-6=12 2002-04-07
From Diane:
I am in 6th grade advanced math and I just started Algebra. My teacher tries to explain it to me but I just can't get it. I am having difficulty understanding it. Please HELP!!! I will type a problem, if you could answer it and show your work so i can understand it that

would be great. Please explain in simple terms.

here is a couple problems I am having trouble with,



Answered by Penny Nom.
Pairs of equations 2002-04-04
From A student:

high school level
student is asking

y=4x x=-4y 
x+y=5 3x+2y=20   

y=x-1 3x-y=4 
x+y=3 2x-3y=-9   


. . . 

Answered by Penny Nom.
Algebra review questions 2002-01-14
From A student:
  1. A wildebeast was observed racing a distance of 86.4m in 4.8 seconds. Find the speed of the wildebeast in m/s.

  2. 8x - 7 - 5x = 23

  3. 7 z - 3 (z + 2) = 26

Answered by Penny Nom.
Two algebra problems 2001-12-24
From Cass:
if the graph of a equation is 2x2 - y2 = 8 passes through point (6,k), find the positive value of k.

if 5x2 - 2 x = 1, find positive value of x

Answered by Penny Nom.
y = zx - x - c 2001-12-11
From Andrew:
Could you please help me work out the value of x where: y = zx - x - c
Answered by Penny Nom.
y= (3x+2)/(4x-5) 2001-12-05
From Courtney:
y= (3x+2)/(4x-5)
solve for x

Answered by Penny Nom.
Two equations in two unknowns 2001-12-04
From Courtney:
y = 3x + 2
y = 4x - 5

solve for x

Answered by Penny Nom.
Solving x^2-3x+5=0 2001-11-30
From Katy:
How do you find the solution to x2-3x+5=0?
Answered by Penny Nom.
Matrix 2001-11-21
From Hoda:
I have a question about matrix multiplication; well, actually, matrix division. I am assuming that matrices are divided the same as they are multiplied; that is, row by column. But what happens if you have to divide by zero? How does this affect the resulting matrix?
Answered by Patrick Maidorn and Penny Nom.
3x-1/2(x-4)+5= -3 2001-11-13
From Tausa:
3x-1/2(x-4)+5= -3
Answered by Penny Nom.
A cubic 2001-11-10
From Louise:
x3 + 9x2 - 7x - 63
Answered by Penny Nom.
1 minus 5(y) equals negative 2 2001-11-10
From Judy:
1 minus 5(y) equals negative 2
Answered by Penny Nom.
8w-15 = 3w-10 2001-11-01
From A student:
8w-15=3w-10, w =?????
Answered by Paul Betts.
Solving trig equations 2001-09-22
From Asad:
Can you please explain to me how to solve trig Equations,e.g sin(x)=x4+12/2+cos(x)=x6+9/3= (if this can be solved)
Answered by Claude Tardif.
Solve for h 2001-09-17
From Kim:
s=2lw+2wh+2hl solve for h
Answered by Penny Nom.
Common solution 2001-06-02
From Samantha:
  1. Solve for common solution: x+y=6 2x-3y=2

  2. Solve for y in terms of x: 3x-y=4

Answered by Penny Nom.
Solving some equations 2001-04-16
From Justin:
Solve the following equations for x
  1. x+7=10

  2. x-7=10

  3. 3x=7

  4. x/3=10

  5. .

  6. .

  7. .

  8. .

Answered by Penny Nom.
(8 + 5)5 = (y + 4)4 2001-04-01
From Kelley:
(8 + 5)5 = (y + 4)4
What is the value of y?

Answered by Penny Nom.
Solving an equation 2001-03-27
From Jennifer:
How would I solve this equation? 1.6 = 2x/(.1-x) - the equation in parenthesises is raised to the second power. I know you take the square root of both sides, but there is where I get lost.
Answered by Leeanne Boehm.
Quadratic equations 2001-03-11
From Philip:
I am a student in the UK and i am in secondary school and i am doing my GCSE next year.

here are my questions:

solve the following equations correct to 2 decimal each time.

[1] 2xsquared + 5x = 1

[2] 3xsquared(2x+1)=1

[3] xsquared + 7x + 2 = 2x + 4

[4] 5xsquared - 3x = xsquared + 4

Answered by Penny Nom.
The substitution method 2001-03-05
From A student:
Solve each system of equations by the substitution method. Show your work.
  1. y = 8
    7x = 1 - y

  2. y = x - 1
    4x - y = 19

Answered by Penny Nom.
What is the value of n? 2001-03-03
From Adam:
When I add n to 7 and then divide my answer by 4,I get 5. What is the value of n?
Answered by Penny Nom.
Solve for the variable 2001-02-28
From Ashley:
I've got 2 questions. We (my dad and I) can not figure them out. please help me.
  1. 21 = 9 - 2 (4a + 2) and I am supposed to find out what the variable is.

  2. 2/3 n + 3/8 n = 15/16 (those are fractions). Again, I need to find out what the variable is.

Answered by Penny Nom.
Solve for two variables 2001-02-25
From A student:
How do I solve for %1 and %2 in the following formula when T1, T2 and T3 are known? %1 and %2 are ratios of the same element, therefore %1 + %2 = 100%

(%1 x T1) + (%2 x T2) = T3

Answered by Penny Nom.
g(g+5)=0 2001-02-20
From Jenna:
g(g + 5) = 0
Answered by Penny Nom.
A problem with distance 2001-01-16
From A student:
For what values of a is the distance between P(a, 3) and Q(5, 2a) greater than the square root of 26.
Answered by Penny Nom.
Completing the square 2001-01-12
From Jacky Lam:
A friend told me that completing square not only can find the vertex but also the roots of a quadratic equation. Is it possible? How? Can you show me how to find the roots of the following equation using completing the square?

8x2 + 8x + 4

Answered by Penny Nom.
Solving x - sin(x) = constant 2000-12-29
From Keith Roble:
If x is in radians, how do you solve for x, where: x-sin(x) = constant?
Answered by Harley Weston.
Solving an equation 2000-12-29
From Bob:
Would you be able to help me solve this math equation..

Solve for b, 2 [b - (q + s)] / q = s

Answered by Penny Nom.
Solving an equation 2000-11-14
From Heather:
4x-3 = 3x+4 these kinds of problems i dont get but everything else in my math class i have got. i just dont understand it.
Answered by Penny Nom.
2-step equations 2000-10-11
From Jen:
i don't get how you find the answer to these equations

140= -4 -12e

x/-2 + 6 = 4

Answered by Penny Nom.
A equation with a square root 2000-09-03
From Lea:
Please help with 2 plus the square root ( and under it has x plus 1) = 6
Thank you

Answered by Penny Nom.
Solving an equation 2000-08-26
From Patrick:
My question is how would u do a problem like this..........
[2x-37] =15?....u have to solve it for absolute value equations....????

Answered by Harley Weston.
Two linear systems 2000-08-01
From A student:
please help me with this homework question. 5/x + 6/y= 19/6 3/x + 4/y =2
hint: let a = 1/x and b = 1/y substitute these expressions into the system to find a and b. Then find x and y.

This is a question I answered wrong on a test: solve the given system for x, y, and z. Express your solutions in terms of a, b, and c.

Answered by Penny Nom.
LOG(LN(x)) = 1 2000-07-28
From An algebra student:
LET F(x)=LOG X AND G(x)= LN X. SOLVE (f *G)(x)= 1

Answered by Harley Weston.
(mn + m + n)/(m^2 + n^2) = 1 2000-07-24
From William:
Find all pair of positive integers m and n such that mn + m + n divides m2 + n2 = 1.
Answered by Peny Nom.
An equation involving x to the x 2000-07-22
From Joy Peter:
I am joy, a teacher teaching Maths at the secondary level and while solving a sum came to this stage when i got xx (1 + log x) = 0, by which we can conclude that xx = 0 or 1 + log x = 0. If xx = 0, than what should be the value of x? I feel that the value of x should then be 0 (zero) but then how do I explain this to the students as we also know that anything to the power of 0 is 1 but here 0 raised to 0 is 1. If this is not defined then how do I explain this?
Answered by Penny Nom.
n! = 42(n-2)! 2000-07-21
From Damon Bailey:
Solve n! = 42(n-2)!
Answered by Paul Betts.
4x - [2x -(3x - 2)] = 13 2000-05-13
From Teresa:
I need to find the following equation.
4x - [2x -(3x - 2)] = 13

Answered by Penny Nom.
A system of equations in five unknowns 2000-03-20
From Will:
I have been having some problem with the following question for some time. I would appreciate any help on solving the problem or a solution.

Q: Assume that a system of equations in the unknowns x1, x2, x3, x4 and x5 when converted to row echelon form gives


Answered by Penny Nom.
Systems of linear equations 2000-03-10
From Ann Marie Devereux:
hi there!!, I guess I have a problem!!!
  • 3x+4y=10 (over)

  • 2x=5y+3 (over)

Answered by Penny Nom.
Some equations 2000-03-08
From Maria:
Hi, could you help me with these questions:

Find x & solve

  • 7-2x/3=9
  • 4x+3/5=-2
  • 6-2x=14
  • -1/7x=-4/3+1/6

Answered by Penny Nom.
Solving an equation 2000-01-17
From Shelley's Mom:

My daughter has an assignment in math that includes this equation:

-6b+5= -10

I've tried to help her with a scale. We've figured that you subtract 5 from each equation so its not -6b = -15. Is this correct and can you help us figure out the next step?

Answered by Penny Nom.
Capacitor discharge rate 2000-01-09
From Bill Phillips:
I need to be solve for t in the following rate problem for an electrical capacitor. Vr = E(e^-t/RC), e=nat. log 2.718 raised to the -t/RC power.
Answered by Harley Weston.
Solving a cubic equation 1999-12-30
From Natalia:
How can I solve:
2 x3 - x2 + x - 2 = 0 ???

Answered by Penny Nom.
Solve for v 1999-12-09
From Beth:
Answered by Penny Nom.
Inequalities and absolute values 1999-12-07
From Austin Cline:
Solve for x: The absolute value of x-1 is less than or equal to the absolute value of x-2
Answered by Harley Weston.
Multiple step problems 1999-11-09
From Maria Rainsdon:
I don't understand how to solve these multiple step problems. I wasn't there when my teacher explained it and I am really lost. Here is one of the probs I don't understand: 3m+6=-m-6.
Answered by Penny Nom.
Equations with fractions 1999-10-10
From Lori:
I'm a secondary student. How would you figure out a problem such as t-2/t =14/3t - 1/3. The book gave one example but it is really easy. The work YOU have to do is totally different. You don't have to tell me the answer just how to do such problems like these.
Answered by Penny Nom.
Two Quadratics 1999-10-08
From Jason On:
Solve the following equations,expressing solutions in the form p + iq.
  1. sqr(x) + 2x - 1 = 0,
  2. sqr(x) + 2x - 3 = 0.

Answered by Harley Weston.
sin x = x/10 1999-10-07
From Amandeep Grover:
Solve the equation sin x = x/10
Answered by Harley Weston.
-8*-(-5a)=15 1999-09-22
From Shelby:

i cannot get this question!! please help me!!
Answered by Harley Weston.

Grade 10 math 1999-04-08
From Ron:
the type of question i'm having trouble with is 5(2x-1)=3(x-4)
Answered by Penny Nom.
Quadratic equations 1999-03-31
From Ken Niebergall:
#1 a2 - 10a = 2a - 36

#2 t(t - 5) = 5 (t - 5)

#3. (x + 4)(x - 3) = 8

Answered by Jack LeSage and Penny Nom.

The Quadratic Formula 1999-01-22
From Eric Morgan:
Hi my name is Eric Morgan and I m in 8th Grade honors math (middle) and I'd like to know how to prove the quadratic formula -bħsqrt of b(a)(c)over 2(a)
Answered by Penny Nom.
Linear Equations 1999-01-16
From Casie Tomney:
My dad and I have been trying to figure, how to solve for x on any of these problems my teacher gives us. The problem is:

2h/3 + 1/2 = 5h/6 - 3/4

Answered by Jack LeSage.

Algebra 1998-11-25
From Casey:
yeah my son brought home a math worksheet and he was wondering and me too if u could help him and me out . he has problems like this 4n+9=7n+2= ??? and he has to show work so if u could help us out that would be great
Answered by Jack LeSage.
A Linear System 1998-10-08
From Jason Bussey:
The linear systems with the following pattern all have the same solution. Is their some kind of reasoning as to why this is so?



The solution is always x=-1, y=2

Thank you
Answered by Penny Nom.

Solving Quadratics 1998-07-16
From Fred Goodrich:
I need a step by step lesson on solving quadratic equations.

Thank you,
Answered by Penny Nom.

Grade 9 Algebra 1998-06-07
From Tarah Kostenko:
I am a grade 9 student and I cannot figure out how to solve these two similar problems. can you please help?
-3(y-1/2)=1/2 also -2/3(x + 1)=6
I don't come up with the same answers as the book and I can't figure out what I'm doing wrong.

Thank you,

Answered by Harley Weston.

Intersecting Lines. 1998-02-10
From Erik Heppler:
My typewriter frequently makes mistakes. Suppose I gave you the following system of equations to solve:

35.26X + 14.95Y = 28.35
187.3X + 79.43Y = 83.29

When I looked back, I realized that I meant to use 14.96 as the "Y" coefficient in the first equation instead of 14.95. Solving the system using 14.95 and then solving another system using 14.96 with all other values the same both times results in the intersection points (1776, -4186) and (-770, 1816) respectively.
How can that be?
Answered by Penny nom.

Find the Numbers. 1997-12-28
From Sandy C:
The sum of the squares of two numbers is 53. Twice the greater, minus the lesser is 11. Find the numbers.
Answered by Penny Nom.
Solving a Trig Equation. 1997-04-28
From Susan Harvey:
Hi I am a teacher and have a calculus problem that I have a solution to but it seems so involved that I would be interested to see if their were other solutions.

Solve for x, if x is from -90 to 90 degrees

tan2x = 8cos{squared}x - cotx
Answered by Chris Fisher Denis Hanson and Harley Weston.

Natural Logarithm Functions 1997-04-23
From Rickson:
The following two questions are some of my son's homework that he is having trouble with......any advice or assistance would be appreciated.

(eX)5=1000.............the X and 5 are exponents

lnx + ln(x+3) = ln10

In each question the problem is to find x.
Answered by Harley Weston.

Will this always yield a palindrome? 1996-08-28
From Andy Golden:
My friend Justin Skywatcher, said that when his children were in 6th grade, they were taught that if you take any number, reverse it and add the two together, a palindrome will result. If not, continue performing the above operations, and a palindrome will eventually result. Will this always yield a palindrome?
Answered by Chris Fisher.



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