Solving 9a)
To find the perimeter of a trapezoid, you add up the all the side lengths.
8+5+6+15.5
Perimeter=34.5
The formula for the area of a trapezoid is:
(Base a+base b)/2*height
Input the information we know:
(8+15.5)/2*4
Follow BEDMAS
23.5/2*4
11.75*4
Area=47 inches²
The area would be 47 inches squared.
Hope this helps!
-Benjamin