2(\frac{Area}{h} ) - b1 = b2
Explanation:
The formula for calculating the area of a trapezoid is the following.
Area = \frac{b1+b2}{2} * h
What we are asked to find is the formula for finding b2. We can do this by rearranging the Area formula and getting b2 by itself on one side.
Area = \frac{b1+b2}{2} * h
\frac{Area}{h} = \frac{b1+b2}{2} .....divide h on both sides
2(\frac{Area}{h}) = b1+b2 .... multiply 2 on both sides
2(\frac{Area}{h} ) - b1 = b2 ....subtract b1 on both sides
Now we have b2 by itself on one side and the formula is rewritten to solve for b2.