72 items are filed under this topic.
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The substitution method |
2020-06-10 |
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From Hardebolar:
simultaneous equation by substitution method
.a-b=2/3
a+b=1 2/3
Answered by p. |
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Solve sinX=0.703X for X |
2018-03-13 |
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From PARAM:
sinX=0.703X
Answered by Penny Nom. |
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A cubic equation |
2016-07-25 |
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From Chinmay:
x³-2x²-7x+5
Answered by Penny Nom. |
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The height of a parabolic arc |
2015-12-30 |
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From Tom:
Is there an algebraic means to determine the highest point of a parabolic arc if the base and perimeter are known?
Answered by Penny Nom. |
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The positive root of sin(x) = x^2 |
2015-12-13 |
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From Kemboi:
Find the positive root of the equation sin(x) = x^2
Answered by Penny Nom. |
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The method of elimination |
2015-05-01 |
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From oreanna:
Question from oreanna, a student:
How do u solve 2x+9y=3
7x-4y=-25 in elimination
Answered by Penny Nom. |
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1/6k=-11 |
2014-11-13 |
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From Marty:
Using the balance method, what is the answer to 1/6k=-11, trying to find what k equals. Thanks
Answered by Penny Nom. |
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The method of elimination |
2014-07-05 |
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From leo:
please explain how can i solve this problem
3x-6y=-38
6x-9y=44
using elimination and simultaneous method thank you :)
Answered by Penny Nom. |
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x - 2 Sin[x] = 0 |
2014-05-08 |
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From chanmy:
please help me to sole this equation x - 2 Sin[x] = 0,thank you
Answered by Penny Nom. |
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n log n = 36 * 10 ^ 12 |
2013-11-12 |
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From shihab:
How to find value of n in this equation :
n log n = 36 * 10 ^ 12
Answered by Penny Nom. |
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Four equations |
2013-08-08 |
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From may:
HI how to solve this 4 equations?
A+C = 0
-4A+B-8C+D=1
3A+16C-8D=-29
-12A+3B+16D=5
Answered by Robert Dawson. |
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Solve sin 3x = -0.1254 with x between o and 360 degrees |
2013-02-21 |
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From David:
sin 3x = -0.1254 0
Answered by Harley Weston. |
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Solve sin 3x = -0.1254 with 0 |
2013-02-21 |
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From David:
sin 3x = -0.1254 0
Answered by Harley Weston. |
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Sinx=logx+x^2 |
2012-11-28 |
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From yasmin:
Sinx=logx+x^2
Answered by Harley Weston. |
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A volume of revolution |
2012-07-15 |
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From Tewodros:
Let f(x) = e^x and g(x) = x^1/2 both be defined on [0,1]. Consider the region bounded by f(x), g(x), x = 0, x = 1. Rotate this region about the y-axis and determine the volume using the shell method.
Answered by Harley Weston. |
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Using Newton's Method to find a root |
2012-04-09 |
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From Nancy:
Use Newton's method to find the real root function, accurate to five decimal places
f(x) = x^5+2x^2+3
Answered by Penny Nom. |
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Four apples and two oranges cost Rs. 30... |
2012-01-13 |
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From nasr:
Four apples and two oranges cost Rs. 30, and one apple and 3 oranges costs Rs.15.How much does each apple and each oranges cost?
Answered by Harley Weston. |
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A volume of revolution |
2012-01-11 |
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From john:
find volume of solid generated by revolving the region in the first quadrant bounded by the curve y squared=x cubed, the line x=4 and the x-axis about the line y=8. The answer in the back of the book is 704 pi divided by5
Answered by Penny Nom. |
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Eliminate y |
2011-04-07 |
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From Lynn:
2x + y = 8
y + 3z =5
z + 2w =1
5w + 3x = 9
Form three equations with y eliminated
Answered by Penny Nom. |
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The percent-day method |
2010-12-04 |
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From Kenneth:
I read about this method in an old business mathematics book and was curious about how it works to produce the correct answer.
“Percent-day method is based on 360 days’ time and 1% interest. Any interest rate multiplied by any number of days is equal to so many %-days.”
Example: 82 days at 5% equals 410%-days.
Answered by Penny Nom. |
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Elimination and substitution |
2010-09-18 |
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From Lauren:
Solve one using the method of substitution and the other with the method of elimination.
v
a. y=5x+4
x=2y+1
b. 4x+3y=7
6x-3y=13
Answered by Penny Nom. |
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A logarithmic equation |
2010-09-08 |
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From Rohit:
x^2 + k*ln(x) - c - k = 0
Where k and c are constants.
Answered by Penny Nom. |
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x/a +y /b =a+b : x/a^2+ y/b^2 =2 |
2010-05-30 |
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From smithu:
x/a +y /b =a+b : x/a2+ y/b2 =2 solve by using elimination method ,
cross multiplication, substitution method
Answered by Penny Nom. |
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Arc length and Chord length |
2010-03-13 |
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From Darryl:
Is there a formula to determine the chord length of an arc knowing only the arc length and the arc depth (sagitta)? I know you can't find the radius with only these two inputs, but can you find the chord length?
Answered by Harley Weston. |
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Substitution method |
2010-02-17 |
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From Melodie:
7x - 4y = -10
4y= x-2
Answered by Tyler Wood. |
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Linear programming using the Simplex Method |
2009-12-28 |
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From William:
A gold processor has two sources of gold ore, source A and source B. In order to keep his plant running,
at least three tons of ore must be processed each day. Ore from source A costs $20 per ton to
process, and ore from source B costs $10 per ton to process. Costs must be kept to less than $80 per day.
Moreover, Federal Regulations require that the amount of ore from source B cannot exceed twice the
amount of ore from source A. If ore from source A yields 2 oz. of gold per ton, and ore from source B
yields 3 oz. of gold per ton, how many tons of ore from both sources must be processed each day to
maximize the amount of gold extracted subject to the above constraints?
I need a linear programming solution or algorithm of the simplex method solution.
Not a graphical solution. Thanks.
Answered by Janice Cotcher. |
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A linear system |
2009-10-20 |
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From marissa:
Solve this linear system
2x-y=5
3x+y=-9
Answered by Penny Nom. |
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541.39(1 + i)^15 = 784.09 |
2009-10-14 |
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From Fitore:
Hi, I noticed that this question was already posted up, however I was hoping I could solve it without having to use logs. Can you please help me? The equation is:
541.39(1 + i)^15 = 784.09
Answered by Penny Nom. |
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Elimination method |
2009-10-08 |
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From Kenty:
How do I solve this problem using the elimination method?
3x-7y=0
6x+4y=0
I am not sure how so if someone can show me a similar problem (instead of
solving this one for me) that would be fantastic.
Answered by Penny Nom. |
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Two equations in two unknowns |
2009-09-18 |
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From Citizen:
x+-3y=7
-x+4y=7
Answered by Penny Nom. |
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The method of substitution |
2009-09-17 |
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From laura:
ok! i really need help with this question plz help!!
x= - 4y +5
x+2y = 7
Answered by Penny Nom. |
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Find the central angle |
2009-08-18 |
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From Larissa:
In a circle, the length of a chord AB is 4 cm and the length of the arc AB is 5 cm. Find the central angle theta, in radians, correct to four decimal places. Then give the answer to the nearest degree. I think I'm supposed to use Newton's method, but am not sure how to start with this problem.
Answered by Harley Weston. |
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Linear systems |
2009-02-20 |
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From Rose:
I have been having trouble trying to figure out these three math problems , I need help breaking them down so I could understand them better please help.
1. x = 7 - x
2 x - y + 8
2. 8 x + 5 y = 1 8 4
x - y = 3
3. y + 2 x = 3
y + 2 x = 4
I can't figure out how to break them down in the right order.
Answered by Penny Nom. |
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The substitution method |
2009-02-18 |
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From Nicolette:
I am working on linear programming problems that I need to solve pairs of linear equations for. I am confused and am not sure how to solve these problems!
5x+3y=7 y=x-3 How can i solve this using the substitution method?
Answered by Penny Nom. |
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The substitution method |
2009-02-06 |
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From amber:
Pleasse help me with this problem
x+y=-2
y-2x=1
Answered by Penny Nom. |
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System of equations - comparison method |
2009-01-02 |
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From nick:
Hi, I am doing a project on system of equations by using comparison method,
but for some reason or another, i can't seem to find any information on the
comparison method at all. So, please would you help me by giving me a website
that you know of that has some information on my method. And, if you know the
answer, can you please tell me why or when do we use system of equations by
using comparison method?
Thank You
Answered by Robert Dawson. |
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The substitution method |
2008-07-26 |
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From Enid:
Solve by substitution method
3x + 7y = 25
-7x + y = 63
Answered by Penny Nom. |
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x^3-6x^2+3x+5=0 |
2008-05-22 |
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From faiz:
x3-6x2+3x+5=0
Answered by Janice Cotcher and Harley Weston. |
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Integrate 2x(x^2-1)^5 dx |
2008-04-17 |
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From joey:
pls help me to integrate
2x(x^2-1)^5 dx using the substitution u=x^2-1
Answered by Harley Weston. |
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Estimate the cube root of 270 |
2008-03-11 |
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From Tom:
(a) By plotting suitable graphs, estimate to one decimal place the cube root of 270.
(b) With reference to your answer to part (a), use 8 iterations of a Bisection Search to refine your estimate. Use the nearest whole numbers either side of your estimate from part (a) as starting values.
(c) Using either of your starting values from part (b) as first guess, use the Newton-Raphson method to find the true value of the root (to 6 decimal places). Repeat using the other starting value from part (b) and compare the two results.
Answered by Harley Weston. |
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How would one find the radius? |
2007-12-29 |
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From Ned:
Given an arc with length of 192 inches (don't know chord length),
and arc height of 6 inches, how would one find the radius?
Answered by Stephen La Rocque and Harley Weston. |
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Solve sin(x)=x^2-x |
2007-12-11 |
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From ming:
is there anyway you can solve
sin(x)=x^2-x without a calculator?
Answered by Stephen La Rocque. |
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Chicken and goat feet |
2007-12-05 |
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From Kim:
Old McDonald raises goats and chickens. The animals have a total of
100 heads adn 360 feet. How many goats and how many chickens does Mr.
McDonald have?
Answered by Stephen La Rocque and Penny Nom. |
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Substitution method |
2007-10-11 |
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From Kevin:
3xx+2y=-36-y=11
Answered by Stephen La Rocque. |
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Two equations in two unknowns |
2007-09-22 |
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From Mary:
Having problems doing this problem, looking for a solution with the work. I would like to see how you got your answer, to see what I was doing wrong.
solve using the substitution method, is there "no solution" or "infinitely many solutions"
4x+y=4
2x+8y=0
Answered by Stephen La Rocque and Leeanne Boehm. |
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The substitution method |
2007-06-23 |
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From mary:
solve the system by the method of substitution:
-5x+2y=-15
4x-y=9
Answered by Stephen La Rocque. |
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Simultaneous equations : the Elimination method |
2007-06-21 |
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From Patricia:
I need to find the value of X and Y using the Elimination method.
5/x + 3/y=4
25/x-2/y=3
Answered by Stephen La Rocque. |
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The substitution method |
2007-05-08 |
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From A student:
I need help on these two problems( substitution method)
-2x+7y=10
x-3y= -3
and
6x-8y= -12
-3x+4y=9
Answered by Penny Nom. |
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A volume of revolution |
2007-04-08 |
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From christina:
find the volume of the solid formed when region bounded by y=x/3, y=2
and the y-axis. it is revolved about the x-axis.
the assignment was to use both the washer method and the shell method
but when i solved for the volume, i got different answers.
i think my shell method is wrong because i know i'm having difficulties
with using "dy" instead of "dx"
here's my work so far:
Answered by Penny Nom. |
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Factoring a trinomial |
2007-03-27 |
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From Kim:
Hi, could you please help me solve this.
3x(squared) +20x - 7
Answered by Leeanne Boehm. |
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The substitution method |
2007-01-31 |
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From Victoria:
how do i solve this problem using the substitution method?
2x-5= -14
-7x+14y= -5
Answered by Stephen La Rocque. |
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The elimination method |
2007-01-31 |
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From Addrianna:
x-2y=2
3x-5y=7
Answered by Stephen La Rocque. |
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A linear system |
2007-01-04 |
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From Harold:
System A (4, 2/3)
2x-3y=6 and x-3y=2
I approached this problem using the addition method.
Could i have found the answer using the graphing method?
Answered by Penny Nom. |
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Linear systems |
2006-09-21 |
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From Alexander:
Hello, i have a math assignment due tonight at midnight and i need some help please
It is using the addition method to solve linear systems
Answered by Penny. |
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The area of a sector and a triangle |
2006-06-23 |
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From Howard:
I thought of the following problem which is similar but much simpler than the tethered goat problem: What is the angle(it is more illustrative in degrees)of arc of a unit circle so that the area between the chord it subtends and the arc length is equal to the area of the triangle with opposite side the subtended chord.
Answered by Stephen La Rocque and Penny Nom. |
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The interior angles of a right triangle |
2006-05-20 |
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From Greg:
I am wondering if there is a way to figure out the interior angles of a right triangle if we know ONLY the side lengths, and the trick is, we CANNOT use arctangent!
Answered by Leeanne Boehm and Penny Nom. |
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GCF, LCM, primes and the ladder method |
2006-01-07 |
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From Linda:
How would I teach both finding the GCF and LCM with prime factors...I recall the ladder method vaguely.???
Answered by Penny Nom. |
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The substitution method |
2004-11-28 |
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From A student:
I Was working and i ran into this problem can you help me solve it using the substitution method?
-3x-2y=-10
x+5y=-27
Answered by Penny Nom. |
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Square roots and inequalities |
2004-10-25 |
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From Waheed:
Q1. What is the simplest way of finding a square root of any number using just a pen and paper? (I am asking this question because I browsed a few sites a didn't find any method that is simpler than the one I use. so I am just curious.)
Q2. Is it possible that you take an equation and turn it into an inequality by performing same mathematical operations on both sides?
Answered by Claude Tardif and Penny Nom. |
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The method of substitution |
2004-09-20 |
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From Kayla:
y=x-1
y=2x-3
Answered by Harley Weston. |
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The substitution method |
2004-02-14 |
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From Keisha:
I need to solve this problem by using the substitution method.
3x+y=1
x=2y+5
Please help me understand the method to solve.
Answered by Penny Nom. |
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Systems of equations |
2003-11-19 |
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From Scott:
I hope that u can help me....I
am a college student taking a class in Pre Calculus.....I have homework
due this Friday and it counts a BIG Percentage on my FINAL grade.....I
am getting mixed up and can not figure out a few problems.....Please help
me.....
Method Of Subsitution
Problem 1. y- 8x = -5
x(squared) + y(squared) = 25
Problem 2. y = x(squared) - 2x - 6
Y = x(squared) - 4
Answered by Penny Nom. |
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Substitution method |
2003-09-14 |
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From John:
Hello, my name is john and while I was finishing up my work I stumbled into these problems. a/4-b=-1
a+b=11
and
6a-b=-5
4a-3b=-8 Thanks a lot. I really need some help :)
John
Answered by Penny Nom. |
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The substitution method |
2002-02-24 |
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From Joe:
whats the answer to this question? 3x+y=11
x+2y=-3 its substitution method i am having alot of trouble figuring it out. send the answer as soon as possible. thank you
Answered by Penny Nom. |
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Solving x - sin(x) = constant |
2000-12-29 |
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From Keith Roble:
If x is in radians, how do you solve for x, where: x-sin(x) = constant?
Answered by Harley Weston. |
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Question about 3rd degree polynomials |
1999-04-23 |
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From Patrick Bryan:
What is the general solution to the equation with the form: a*x^3 + b*x^2 + c*x + d = 0 I have once seen a solution to this a few years ago, but I do not recall if it was a general solution. What I do know, is that you could simplify this equation to: a*x'^3 + p*x' + q = 0...
Answered by Doug Farenick. |
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Duplation method of multiplication |
1998-11-26 |
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From Sara Whitford:
I am wondering why 16 and multiples of 16 do not work in the ancient duplation method of multiplication used by the Egyptians. I discovered the method in the Journeys math text gr 7 level. Just curious. Am I doing something wrong??
Answered by Jack LeSage and Harley Weston. |
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Linear systems of equations |
1998-11-16 |
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From Crystal Girvan:
My name is Crystal Girvan.Im in grade 11. I have a question.We are solving linear systems of equations: comparison method. My questions is. it says a)use the method of comparison to solve this system a=b-1, 3a+ b=3 b) verify your solutin in a I dont understand it. please help
Answered by Jack LeSage. |
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Operations Research |
1998-10-08 |
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From Lisa Barrett:
What is the history of operations research and the study of linear programming?
Answered by Judi McDonald. |
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Volumes |
1998-08-29 |
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From Lorraine Wall:
Consider the region in the first quadrant bounded by the x and y axes, the vertical line x=3 and the curve y = 1 / (x squared + 3). Determine the volume of the solid by rotating this region about the x-axis. Now that is the first part.
I then have to find the coordinates of the centroid of the solid by rotating this region about the x-axis. Thanks.
Lorraine
Answered by Harley Weston. |
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Volumes of Revolution |
1998-07-24 |
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From Lorraine Wall:
I'm on the section fpr The Computation of Volumes of Solids of Revolution and the following question is giving me problems: -Consider the region in the first quadrant bounded by the x-and y-axes, the vertical line x=3, and the curve y=1/(xsquared + 3) I can determine the volume of the solid by rotating the region about the y-axis using the shell method but I can't seem to be able to get started with the volume when rotated about the x-axis.
Answered by Harley Weston. |
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Cardano's method |
1996-03-11 |
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From Mike Gorski:
What is Cardano's method for finding the roots of a cubic equation?
Answered by Harley Weston. |
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