Answer:
x=14/39, y=-121/39. (14/39, -121/39).
Step-by-step explanation:
7x+5y=-13
-2x-7y=21
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2(7x+5y)=2(-13)
7(-2x-7y)=7(21)
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14x+10y=-26
-14x-49y=147
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-39y=121
y=121/-39
y=-121/39
-2x-7(-121/39)=21
-2x+847/39=21
-2x=21-847/39
-2x=819/39-847/39
-2x=-28/39
2x=28/39
x=(28/39)/2
x=(28/39)(1/2)
x=28/78
simplify
x=14/39
