Hey there! :)
First, find the area of the rectangle
Formula = l · w
l = 16
w = 8
16 × 8 = 128
Now, find the area of the triangle
Formula = (b · h) ÷ 2
b = 4
h = 6
(6 · 4) ÷ 2
↓
24 ÷ 2 = 12
Add both areas
128 + 12 = 140
The area is 140 sq. ft
Hope this helps :)