Answer
y=4
Work Step by Step
We fist combine like terms to obtain that: $-1=-2y+7$. We need to get the y alone, so we cancel out the addition by subtracting 7 on both sides. This leaves us with the equation $-2y=-8.$ We cancel out multiplication by using division, so we divide both sides of the equation by -2 to get that y=4. We plug 4 in for y and confirm that our answer is, indeed, correct.