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Question 275815: find value of x and y
1.) 2x+5y=-9
3x-4y=-2
2.) 4x+13y=40
4x+3y=-40
3.) 2x-3y=-15
y=x-2
4.)2x-3y=-15
x=4y
5.)x+y=14
x=6y
6.)y=x-2
7y-4x=10
i would really like to know these answers to this equations please!!!
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! find value of x and y
1.)
2x+5y=-9
3x-4y=-2
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Multiply 1st Eq by 3 ; Multiply 2nd Eq by 2
6x + 15y = - 27
6x - 8y = -4
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Subtract 2nd from 1st and solve for "y":
23y = -23
y = -1
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Substitute into original #1 and solve for "x":
2x + 5(-1) = -9
2x = -4
x = -2
Ans: (-2,-1)
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2.)
4x+13y=40
4x+3y=-40
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Subtract 2nd from 1st:
10y = 80
y = 8
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Substitute into 4x+3y = -40 to solve for "x":
4x + 3(8) = -40
4x + 24 = -40
4x = -64
x = -16
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Ans: (-16,8)
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3.)
2x-3y=-15
y=x-2
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Substitute for "y" and solve for "x":
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4.)
2x-3y=-15
x=4y
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Substitute for "x" and solve for "y":
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I'll leave the rest to you.
Cheers,
Stan H.
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5.)x+y=14
x=6y
6.)y=x-2
7y-4x=10
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