How do you solve 7x-y=12 and -3y=7x+8

Use the addition method
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1 Answer

7x appears in both equations so we can write 7x=12+y and then substitute in the other equation:

-3y=12+y+8, 0=20+4y, 4y=-20, y=-5 so 7x=12-5=7 and x=1.

Solution: x=1, y=-5.

by Top Rated User (1.2m points)

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