## Geometry: Common Core (15th Edition)

30 $ft^{2}$
Find the height by using the Pythagorean Theorem: $a^{2}$+$b^{2}$=$c^{2}$ $3^{2}$+$b^{2}$=$5^{2}$ 9+$b^{2}$=25 $b^{2}$=16 b=4 (This is your height of the trapezoid.) We use the formula for the area of a trapezoid to obtain: A=$\frac{1}{2}$h($b_{1}$+$b_{2}$) A=$\frac{1}{2}$(4)(6+9) A=$\frac{1}{2}$(4)(15) A=30