Question

Solve by substitution
-4x+y=6
-5x-y=21

Answer 1

x=-3, y=-6. (-3, -6).

Explanation:

-4x+y=6

-5x-y=21

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-9x=27

x=27/-9

x=-3

-5(-3)-y=21

15-y=21

y=15-21

y=-6