Explanation:
The figure is made up of an 8x8 square and 4 identical triangles with 8-ft bases and 4 ft in height. Each triangle has an area = (1/2)bh = (1/2)(8)(4) = 16 ft^2. The square part has an area of 8x8 = 64 ft^2. Therefore, the total area of the figure is
A = (area of square) + 4×(area of triangle)
= 64 ft^2 + 4(16ft^2)
= 128 sq ft