Answer:
area = 697.5 ft²
Explanation:
Think of an outer large rectangle minus a smaller upper rectangle.
area = LW - lw
area = (45 ft)(20 ft) - (45 ft - 10 ft - 8 ft)(7.5 ft)
area = 900 ft² - (27 ft)(7.5 ft)
area = 900 ft² - 202.5 ft²
area = 697.5 ft²