You have to evaluate the area of the circle and the area of the trapezoid. Then you substract the area of the circle from the area of the trapezoid.
Area of circle :
[tex]\pi {r}^{2} = 16\pi[/tex]
Area of trapezoid : (b + B)h/2 = 17*8/2 = 68
The area of the shaded portion is
[tex] 68- 16\pi[/tex]
