Chapter 2 - Solving Equations - 2-2 Solving Two-Step Equations - Practice and Problem-Solving Exercises - Page 91: 17

$h=-27$

We need to get the h alone, so we cancel out the addition by subtracting 10 on both sides. This leaves us with the equation $h/3=-9$. We cancel out division using multiplication, so we multiply both sides by 3 to get that h=-27. We plug -27 in for h and confirm that our answer is, indeed, correct.