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Question 429681: 2x-3y=21
y=3-x
x=4-5y
3x+15y=-1
5x-2y=14
y=2x-5
help me solve these for my test tomorrow
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 2x-3y=21
y=3-x
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Substitute for "y" and solve for "x":
2x-3(3-x) = 21
2x-9+3x = 21
5x = 30
x = 6
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Solve for "y":
y = 3-x
y = 3-6
y = -3
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x=4-5y
3x+15y=-1
Substitute for "x" and solve for "y":
3(4-5y)+15y = -1
12-15y+15y = -1
12 = -1
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There is no solution for this system of 2 equations.
There is no point (x,y) that satisfies both equations.
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5x-2y=14
y=2x-5
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Substitute for "y" and solve for "x":
5x - 2(2x-5) = 14
5x -4x+10 = 14
x = 4
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Solve for "y":
y = 2x-5
y = 2*4-5
y = 3
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Cheers,
Stan H.
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