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3 votes
Substitute

-3x-8y=4
-2x+7y=15

User ByeBye
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1 Answer

2 votes
-2x=15-7y
x=-7.5+3.5y

-3x-8y=4
-3(7.5+3.5y)-8y=4
-22.5-10.5y-8y=4
-22.5-18.5y=4
-18.5y=4+22.5
-18.5y=26.5
y=-53/35

the fraction might not be in lowest terms.
User JuicyFruit
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