Respuesta :

2x-y=8...(1)
x+y=7....(2)

from (2)
y=7-x....(3)

put (3) into (1)
2x-(7-x)=8
2x-7+x=8
2x+x=8+7
3x=15
x=5.....(4)

put (4) into (2)
x+y=7
5+y=7
y=7-5
y=2

Hope it helps c:
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