The area for a trapezoid is given by the formula below, where a and b are the lengths of the two bases and h is the height of the trapezoid.
A = h ( a + b ) / 2

If the area of a trapezoid with base b measuring 8 feet is 16.5 square feet and base a measuring the same length as the height, then what is the height of the trapezoid?
A.
7 feet
B.
4 feet
C.
3 feet
D.
9 feet