Question

calcule y+9 - 9-2y = y
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5 10 2

Answer 1

y+9-9-2y=y
y-2y-y=-9+9
2y=0
y=2/0=0
eu acho que está certa! :)

Answer 2

y+9-9 -2y=y
isolando o y:
y-2y-y=-9+9
-2y=0
.(-1)-y=0/2 .(-1)
y=0