Answer
$b=-15/2$
Work Step by Step
We first combine like terms to get that $-2b-5=10$. We now need to get the b alone. Thus, we cancel out the subtraction by adding 5 on both sides. This leaves us with the equation $-2b=15$. In order to cancel out multiplication, we use division, so we divide both sides by -2 to get that $b=-15/2$. We plug -15/2 in for b and confirm that our answer is, indeed, correct.