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3 years ago

Solve the following system : -x + 5y = 8 and 3x + 7y = -2

Mathematics

1 answer:

poizon [28]3 years ago

4 0

-x + 5y = 8

multiply this equation by 3

-3x + 15y = 24

now add it to the other equation ( elimination)

-3x + 15y = 24

3x + 7y = -2

-----------------------

0x + 22 y = 22

divide each side by 22

y =1

substitute into -x + 5y =8 to find x

-x + 5(1) = 8

-x + 5 = 8

-x =3

divide by -1

x =-3

Answer (-3,1)

Choice A

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