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Solve the following system by any method. –8x – 8y = 0 –8x + 2y = –20

A. (2, 2) B. (0, –2) C. (–2, 2) D. (2, –2)

1 Answer

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this one is simple since we already have the two x variables.equal. All we have to do is subtract the equations from one another to get the answer.
So i will subtract the left side by the other left side and the right side by the other right side

-8x - 8y -(-8x + 2y) = 0 -(-20)

distribute negative sign

-8x - 8y + 8x - 2y = 0 + 20

do the math
- 10y = 20
Y = -2

plug t into an equation
-8x -8 (-2) = 0

-8x + 16 = 0
-8x = -16
x = 2
answer (2, -2)
User Adam Siemion
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