SOLUTION: 3x+4y=200 2x=3y=144

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Question 660574: 3x+4y=200
2x=3y=144
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
3x%2B4y=200
2x=3y=144...you probably need + sine between 2x and 3y
Start with the given system of equations:
3x%2B4y=200....1
2x%2B3y=144.......2
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So let's solve for y on the first equation

3x%2B4y=200 ....subtract 3x from both sides

4y=200-3x

y=-%283%2F4%29x%2B200%2F4

y=-%283%2F4%29x%2B50........plug it in 2 and find x

2x%2B3%28-%283%2F4%29x%2B50%29=144.......2

2x%2B%28-%283%2A3%2F4%29x%2B50%2A3%29=144

2x-%289%2F4%29x%2B150=144

2x-%289%2F4%29x=144-150

2x-%289%2F4%29x=-6......both sides multiply by 4

8x-9x=-24

-x=-24.....both sides multiply by -1

highlight%28x=24%29


now find y

y=-%283%2F4%29x%2B50...plug in x

y=-%283%2F4%2924%2B50

y=-%283%2Fcross%284%29%29cross%2824%296%2B50

y=-%283%29%2A6%2B50

y=-18%2B50

highlight%28y=32%29



or, with a grid: