Answer:
50 ft²
Step-by-step explanation:
The figure is a trapezium with area (A) calculated as
A = [tex]\frac{1}{2}[/tex] h(a + b)
where h is the perpendicular height and a, b the parallel bases
Here h = 5, a = 12, b = 8, thus
A = 0.5 × 5 ×(12 + 8) = 0.5 × 5 × 20 = 50 ft²