To determine the area of the trapezoid we need to use the following expression:
[tex]A=\frac{B+b}{2}\cdot h[/tex]Applying the dimmensions given in the problem we can calculate the area as shown below:
[tex]A=\frac{5+4}{2}\cdot4=\frac{9}{2}\cdot4=\frac{36}{2}=18\text{ square inches}[/tex]The area of the trapezoid is 18 square inches.
