Answer
$b_2=\frac{2A}{h}-b_1$
Work Step by Step
The given formula is
$\Rightarrow A=\frac{1}{2}h(b_1+b_2)$
Multiply each side by $2$.
$\Rightarrow 2\cdot A=2\cdot \frac{1}{2}h(b_1+b_2)$
Simplify.
$\Rightarrow 2 A=h(b_1+b_2)$
Divide each side by $h$.
$\Rightarrow \frac{2A}{h}=\frac{h(b_1+b_2)}{h}$
Simplify.
$\Rightarrow \frac{2A}{h}=b_1+b_2$
Subtract $b_1$ from each side.
$\Rightarrow \frac{2A}{h}-b_1=b_1+b_2-b_1$
Simplify.
$\Rightarrow \frac{2A}{h}-b_1=b_2$
Hence, the solution is $b_2=\frac{2A}{h}-b_1$.
