532m²
This is a compound shape. Split it into 3 shapes.
Area of a square = L²
L = 18
18² = 324
324m²
Area of a triangle = 1/2bh
b = 18
h = 16
18 × 16 × 1/2 = 144
144m²
Area of a triangle = 1/2bh
b = 8
h = 16
8 × 16 × 1/2 = 64
64m²
324 + 144 + 64 = 532