Answer
$b=-8$
Work Step by Step
We need to get the b alone. In order to cancel out division, we use multiplication, so we multiply both sides by 5 to get that $b+3=-5$. We now cancel out the addition by subtracting 3 on both sides, giving us a final answer of $b=-8.$ We plug -8 in for b and confirm that our answer is, indeed, correct.