Help!

3. A trapezoid has an area of 166.5 in.², a height of 9 in., and one base measuring 15 in. What is the length of the other base? (1 point)
3.5 in.
7 in.
18.5 in.
22 in.

Question

Help!

3.   A trapezoid has an area of 166.5 in.², a height of 9 in., and one base measuring 15 in. What is the length of the other base?  (1 point)
3.5 in.
7 in.
18.5 in.
22 in.

directrix · Answer

The area of a trapezoid is found by taking (1/2) of its height and multiplying the result by the sum of the two bases of the trapezoid.

directrix · Answer

In this case,

166.5 = (1/2) * 9 (15 + b) where b is the unknown base.
333 = 9* (15 + b)
Divide both sides of the equation by 9 and solve for b.