Answer:
(-5, -8)
Step-by-step explanation:
-3x+3y=-9
-3x+y=7
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simplify -3x+3y=-9 into x-y=3
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y=x-3
-3x+y=7
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-3x+(x-3)=7
-3x+x-3=7
-2x-3=7
-2x=7+3
-2x=10
x=10/-2=-5
y=-5-3=-8
x=-5, y=-8
