this is solving systems of equations by elimination, though I am a bit confused
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Answer:
x=7
y=-1
Step-by-step explanation:
4x+8y=20
-4x+2y=-30
8y=20-4x
y=(20-4x)/8
substitute
-4x+2(20-4x)/8=-30
-4x+(40-8x)/8=-30
-4x+5-x=-30
-5x=-35
x=7
4(7)+8y=20
8y=-8
y=-1