## Algebra 1: Common Core (15th Edition)

Given: $A=\frac{1}{2}(b_1+b_2)h$ Multiply both sides with $\frac{1}{2}$: $\frac{1}{2}A=(b_1+b_2)h$ Divide both sides by $(b_1+b_2)$: $\frac{A}{2(b_1+b_2)}=h$ Hence, the correct answer is C.