82 items are filed under this topic.
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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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Augmented matrix |
2011-12-14 |
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From Britney: Write Augmented matrix and use row reduction to solve.
I need major help with this problem! Tomorrow is my semester test and I have no idea how to do this.
2x+5y=8
y-x=10 Answered by Robert Dawson. |
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Linear equations |
2011-10-06 |
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From Hannah: I am confused about a question on my homework, here is an example on what I need to do:
You own a sightseeing boat tour. Kids' admission costs $5, adults' admission costs $8.
During that day you get (made-up number) $521 with 71 admissions.
How many of each passenger boarded?
I tried something like
5x + 8y = 521
x + y = 71
But, I still don't understand how to solve it! Help? Answered by Penny Nom. |
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What is the speed of each car? |
2010-11-04 |
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From Jennifer: two cars are 420 miles apart and traveling towards each other along the same road. They meet in 3.5 hours. One car is traveling 15mph slower than the other. What is the speed of each car?
This must be solved using a system of equation, I have no idea? Answered by Stephen La Rocque. |
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A linear system |
2010-10-15 |
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From Sandy: HARD!! algebra (Linear Systems) question?
An Airplane cruises at 120km/h in still air. One day, when the wind was blowing steady from the west, the airplane travelled west (flying into the wind) and landed at its desination after 1.5h. The airplane's return trip (flying with the wind) was only 1.0 h long. On both legs, the airplane travelled at its cruising speed. (meausred with respect to the air surrounding the airplane).
Part A
Write a System of equations that would allow you to determine the speed of the wind blowing that day and the distance travelled each way
Part B
When solving the system of equations graphically, what equations would you enter into the equation editior (to make graphs on your calculator)
Part C
Indicate what the X and the Y represent Answered by Stephen La Rocque. |
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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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A system of equations |
2010-03-30 |
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From samantha: the equations of two lines are 6x-y=4 and y=4x +2.what is the value of x in the solution for this system of equations? Answered by Penny Nom. |
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The sides of a 30-60-90 triangle |
2010-03-29 |
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From maris: Find the sides of a 30-60-90 triangle whose perimeter is 6. The solution must use systems of equations using 3 variables. Answered by Penny Nom. |
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A quadratic equation |
2010-03-15 |
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From rachelle: under certain condition, it is found that the cost of operating an automobile as a
function of speed is approximated by a quadratic equation. use the data shown
below to find the function. then use the function to determine the cost of operating
the automobile at 60mph.
speed
(in miles per hour) |
operating cost
per mile(in cents) |
| 10 |
22 |
| 20 |
20 |
| 50 |
20 |
Answered by Penny Nom. |
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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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Substitution |
2010-02-14 |
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From Izayah: what is 3 ways to find the meeting point of y=2x+4 and 3x+y=7
by making 2 table and using a graph Answered by Stephen La Rocque. |
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A word problem |
2009-10-24 |
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From Ryan: Two times one number plus 7 times another number is equal to 17. the first number plus the second number is equal to 25. What are the two numbers? Please Help! Answered by Penny Nom. |
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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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$6.25 in nickels quaters and dimes |
2009-10-10 |
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From miriam: a piggy bank contains $ 6.25 in nickles quaters and dimes.
there are 65 coins all together and there are four times as many nickles as quaters
find the number of coins of each kind Answered by Penny Nom. |
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Two rectangles |
2009-10-08 |
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From Lillian: A rectangle is 5cm longer than twice its width.
The width of another rectangle is 3cm less
than the width of the first rectangle and its length is 6cm more than 3 times its
width. If the perimeters are equal, find the dimensions of both rectangles 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 |
2009-07-30 |
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From Alicia: I need help with the following equation please show me the steps to complete so that I will know how to do this my self.
2x-y=2 5x+y=5 Thanks for the help Answered by Penny Nom. |
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Two equations |
2009-05-31 |
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From tony: y = 1.2x - 32.7,
y = -0.7x + 46.15
can you please solve this for me? i am not able to figure it out... thank you
tony Answered by Penny Nom. |
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Two equations |
2009-05-18 |
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From Bob: solve the system:
x/2 - 2y= -8
3x + 2/3y= -10 Answered by Stephen La Rocque. |
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An infinite number of solutions |
2009-03-24 |
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From Sean: this is a linear equations problem;
first:
3535.5 + Fbd (.866) + Fbc (.5) - Fab (.5) = 0
and
-3535.5 - Fab (.866) - Fbc (.5) - Fbd (.5) = 0 Answered by Harley Weston. |
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A linear system |
2009-03-13 |
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From Rasanga: Use the row echelon form of the augmented matrix to solve the following linear system.
X1+2X2+X4=6
X3+6X4=7
X5=1 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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A linear system |
2008-10-22 |
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From Tiffany: solve:
x + y + z = 4
2x - 3y - z = 1
4x + y - 2z = 16 Answered by Penny Nom. |
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Two equations in two unknowns |
2008-10-17 |
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From Dushayne: Please help me in solving this problem:
a. 3x-4y=32
5x+2y=10
b. 2x+3y=11
4x+3y=10 Answered by Penny Nom. |
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Using the augmented matrix |
2008-10-17 |
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From Karlena: I am supposed to write the augmented matrix of the system and use the matrix method to solve the system. I must show my work algebraically
x+y+2z=30
2x+3y+2z=53
x+2y+3z=47 Answered by Harley Weston. |
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The vertices of a triangle |
2008-09-27 |
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From T.: how do you find the coordinates of the vertices of the triangle with the sides determined by the graphs of the following equations:4x+3y+1=0,4x-3y-17=0,4x-9y+13=0? Answered by Harley Weston. |
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A word problem with three numbers |
2008-09-02 |
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From Wanda: "Jabari is thinking of three numbers. The greatest number is twice as big as the least number. The middle number is three more than the least number. The sum of the three numbers is 75. Find the numbers." Answered by Victoria West. |
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Two equations in two unknowns |
2008-08-01 |
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From James: Question from james, a student:
3x+2y=9;24x-2y=18
My math teacher says that it is (2,-4)
Can someone please explain how to figure this out by graphing? Answered by Victoria West. |
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Simultaneous equations |
2008-07-23 |
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From Franco: Solve
3 D + E - F = -10
-2 D - F = -4
-3 D - 4 E - F = -25
Franco Answered by Penny Nom. |
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A rectangular room |
2008-06-30 |
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From Peter: A rectangular room has a perimeter of 42 feet and an area of 108 square feet. What is the length, in feet, of the shorter side? Answered by Penny Nom. |
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How old are the sisters? |
2008-05-11 |
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From George: Theresa is four years older than her younger sister Joni. Twelve years ago, she was twice as old as her sister.
Find the present age of the two siblings. Answered by Penny Nom. |
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A linear system |
2008-03-10 |
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From sandhiya: one group of people purchased 10 hotdogs and 5 soft drinks at a cost of
$12.50. a second group bought 7 hotdogs and 4 soft drinks a ta cost of $9.00
find the cost of a single hot and a single soft drink.(using the row echelon form to solve) Answered by Penny Nom. |
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Simultaneous equations |
2008-02-29 |
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From CONOR: I was wondering if you could help me with this problem
7x - 5y = -1
3y = 4x Answered by Penny Nom. |
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A inear system |
2008-02-03 |
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From Kelly: is (-1,5) a solution of each system? y=-x+4 y=-1/5x Answered by Penny Nom. |
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Two equations in x and y |
2008-02-01 |
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From leslie: 6x+8y=40 4x+5y=25 Answered by Penny Nom. |
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A linear system |
2008-01-22 |
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From Lisa: I am supposed to use augmented matrices to solve this system of equations. x - 3y = 5; 4x - 12y = 13. I think it is unsolvable but I want to be sure I am not just giving up. Thanks in advance for your help! Lisa. Answered by Stephen La Rocque and Brennan Yaremko. |
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Linear systems |
2008-01-10 |
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From Sandra: I have two questions. Please solve both. Thank you.
1.) In your chemistry class, you have a bottle of 5% boric acid solution and a bottle of 2% boric acid solution. You need 60 milliliters of a 3% boric acid for an experiment. How much of each solution do you need to mix them together?
2.) You plant a 14-inch hemlock tree in your backyard that grows at a rate of 4 inches per year and an 8 inch blue spruce that grows at a rate of 6 inches per year. In how many years after you plant the trees will the trees be the same height? How tall will each tree be?
Thank you. I did not understand neither problem, so I could not show any work. Please help. Answered by Stephen La Rocque and Harley Weston. |
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Donuts and bagels for the first period class |
2008-01-08 |
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From Karen: Mr. Pace bought breakfast for his first period class. Ten donuts and fifteen bagels
cost a total of $15.75. Mrs. Pace bought breakfast for her class. Five donuts and twenty
bagels cost a total of $17.00. Set up and solve a system of linear equations to determine the cost
of one donut and one bagel. Answered by Penny Nom. |
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What is the speed of the plane in still air? |
2008-01-05 |
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From oscar: A plane flies 400 miles with the wind and 340 miles against the wind
in the same length of time. If the speed of the wind is 24mph, what is
the speed of the plane in still air? Answered by Penny Nom. |
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An augmented matrix |
2007-11-29 |
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From Beth: I am having troubles fiinding this augnmented matrix. I know how to do it
but everytime i do it it get a different answer and its not the right answer.
Could you help me to make sure I do it right?
Here is the problem:
4x - 3y = 5
2x +9y = 6 Answered by Harley Weston. |
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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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A nonlinear system |
2007-08-14 |
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From Marsia: Explain how the solution of a nonlinear system could be just a point, or two points. Sketching these may make it easier Answered by Penny Nom. |
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Linear systems and inverses |
2007-08-06 |
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From Marsia: explain how inverses are used to solve linear systems. Answered by Penny Nom. |
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A linear system |
2007-06-29 |
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From Kim: solve for x,y,z
x-y+z=4
2x+2y-z=-2
x-2y+2z=7 Answered by Harley Weston. |
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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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A system of linear equations |
2007-06-14 |
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From Alfredo: A student club sponsored a jazz concert and charged $3 admission for students, $5 for faculty, and $8 for the general public. The total ticket sales amounted to $2542.
Three times as many students bought tickets as faculty. The general public bought twice as many tickets as did the students. Set up the equations that determine how many
tickets were sold to each group and solve. Answered by Stephen La Rocque and Penny Nom. |
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What happens when you have zero's on both sides? |
2007-06-05 |
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From Lily: On the substitution method what happens when you have zero's on both
sides of the equation? Is that considered no solution or infinitely many? Answered by Stephen La Rocque and Penny Nom. |
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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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The vertices of a triangle |
2007-05-02 |
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From natakie: Find the coordinate of the vertices of a triangle whose sides lie on the following three lines.
2x+5y-16=0, 4x-3y-6=0 and 3x+y+2=0 Answered by Penny Nom. |
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Two equations |
2007-04-29 |
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From lavon: I'm having trouble figuring out a linear equation, can you help?
- 3x + 2y = 8
3x + 2y = 8 Answered by Penny Nom. |
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A linear system |
2007-04-25 |
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From Tee: 2x -y =5
2x +=y =5
and also
3/7x + 5/9y =27 (fractions)
I have to find the addition method to both problems Answered by Penny Nom. |
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No solution to a linear system |
2007-04-09 |
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From Ryan: When is it possible to get no solution when solving a linear system? Answered by Leeanne Boehm, Steve La Rocque, Penny Nom and Melanie Tyrer. |
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A linear system |
2007-03-23 |
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From Adam: Solve the system by graphing: 4y>6x
-3x+2y<-6 Answered by Stephen La Rocque and Penny Nom. |
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Simultaneous equations with fractions |
2007-02-28 |
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From Alyca: Hello Math Central, I am a grade 10 student taking Academic math. Our unit right now is method of substitution and elimination. I'm stuck on this one question that I've been doing forever. Please help =)
*For this equation I have to do method of elimination, but it's so much harder with fractions...could some one please explain to me how to do it step by step?* x y 2 -- - -- = - -- 3 6 3 x y 1 -- - -- = 1--- 12 4 2
Answered by Steve La Rocque and Ashley Mang. |
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An augmented matrix |
2007-02-13 |
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From Mary: I've been trying for quite some time now to figure this out. I have to solve this by using the Gauss-Jordan Method: 3x - y = 15 2x + 3y = 10 Can anyone help me? Answered by Penny Nom and Gabriel Potter. |
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Patrick's new job |
2007-02-02 |
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From kathy: patrick has been offered jobs by two different automobile repair shops. his income from the first shop will be $1,200 per month plus 3% of the monthly sales. the second shop will pay patrick $1,500 per month plus 2% of the monthly sales. part a let s equal the amount of monthly sales and i equal patrick's income in dollars. write a system of two equations that could be used to determine the monthly income from either shop. part b solve the equation to determine what amount of monthly sales for each shop would result in patrick earning the same monthly income, i, from both shops Answered by Penny Nom. |
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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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Points of intersection |
2007-01-18 |
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From Mark: Find the points of intersection of the given pair of curves. 2x - 3y = -8 and 3x - 5y = -13 Answered by Steve La Rocque and Haley Ess. |
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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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Three people go to a store where there is a sale |
2006-05-30 |
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From Geocee: Three people go to a store where there is a sale. One person buys two shirts, one pair of pants and one sweater. The second person buys one shirt, two pairs of pants and two sweaters. The third person buys three shirts and four pairs of pants. Find the price of each item if the first person spent $155 and the second and third person spent $235 each. Answered by Stephen La Rocque. |
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2x+3y=0 and 3x-y=0 |
2006-03-14 |
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From Lisa: my name is lisa I am doing math for work and i have a math problem to solve and i need help with it here is the question 2x+3y=0 and 3x-y=0 this is one question can you help me please Answered by Penny Nom. |
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Simultaneous Equations |
2005-12-21 |
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From Matt: I have these two equations,
336 = 60a + 10b
and
432 = 84a + 6b
Am I right in saying both a and b are 4.8? Answered by Penny Nom. |
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Solving a pair of equations |
2005-11-10 |
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From Steven: what is answer to
2 x + y = 1
y = -1/3 x - 4 Answered by Penny Nom. |
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The substitution method |
2005-06-28 |
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From Addie: how do i know where to began the substitution method? how do i solve
y = x + 1
2x - y = 1 Answered by Penny Nom. |
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Two equations in two unknowns |
2003-02-06 |
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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. |
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The intersection of conics |
2002-12-19 |
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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. |
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x + y=80 and x + z=100 |
2002-11-28 |
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From PJ: x + y=80 x + z=100 can you solve for x, y or z? Answered by Penny Nom. |
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The substitution method |
2002-11-15 |
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From A student: Solve by using the substitution method. x = 3y - 1 x + 2y = 9 Answered by Penny Nom. |
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Determining a parabola |
2002-11-06 |
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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. |
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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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Simultaneous equations |
2001-12-17 |
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From Matthew: 4x + y = 4 2x - 3y = 5 what is x and y Answered by Penny Nom. |
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Two equations in two unknowns |
2001-12-04 |
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From Courtney: y = 3x + 2 y = 4x - 5
solve for x Answered by Penny Nom. |
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Matrix |
2001-11-21 |
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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. |
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Common solution |
2001-06-02 |
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From Samantha:
- Solve for common solution: x+y=6 2x-3y=2
- Solve for y in terms of x: 3x-y=4
Answered by Penny Nom. |
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Matrices |
2001-03-26 |
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From Peg: What are some applications of matrices, basic trigonometry, and linear systems in the real world? I'm writing and Algebra report about where these topics are used outside of the classroom. Answered by Judi McDonald and Walter Whiteley. |
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Systems of equations |
2001-03-16 |
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From joy: How do u solve problems using systems of equations? ~ finding x and y~ ex:
26 = 3x - 2y 42 = 4x + y Answered by Penny Nom. |
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The substitution method |
2001-03-05 |
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From A student: Solve each system of equations by the substitution method. Show your work. - y = 8
7x = 1 - y
- y = x - 1
4x - y = 19 Answered by Penny Nom. |
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Solving Equations |
2001-02-23 |
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From Stephanie: Do you know who came up with solving equations? Do you have any web-sites that can give me good information on solving equations? Do you know any history on solving equations? Do you know what solving equations is used for? And finally............Sorry about all of the questions :) Has the form of solving equations changed from the time it came out to now? Answered by Juci McDonald. |
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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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A Linear System |
1998-10-08 |
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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? 2x+3y=4 3x+4y=5 4x+5y=6 5x+6y=7 The solution is always x=-1, y=2 Thank you Jason Answered by Penny Nom. |
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