Answer:
x=5, y=8. (5, 8).
Step-by-step explanation:
3x+5y=55
5x+4y=57
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5(3x+5y)=5(55)
-3(5x+4y)=-3(57)
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15x+25y=275
-15x-12y=-171
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13y=104
y=104/13
y=8
3x+5(8)=55
3x+40=55
3x=55-40
3x=15
x=15/3
x=5
