9514 1404 393
Answer:
340 ft^2
Explanation:
The length of one side is 1/4 of the perimeter, so is 10 ft.
The area of the base is the square of the length of the side:
base area = (10 ft)^2 = 100 ft^2
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The lateral area is the area of four triangles, each with a base of 10 ft and a height of 12 ft.
lateral area = 4(1/2)(10 ft)(12 ft) = 240 ft^2
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The total surface area is the sum of the base area and the lateral area:
surface area = base area + lateral area
surface area = (100 ft^2) +(240 ft^2) = 340 ft^2