Answer :
Answer:
79.9 cubic feet
Step-by-step explanation:
You want the volume in cubic feet of a right triangular prism that is 8 inches deep and has triangular faces with a short leg of 12 feet and an adjacent acute angle of 59°.
Long side
The long side of the right triangle can be figured using the tangent function:
Tan = Opposite/Adjacent
Opposite = Adjacent × Tan
long side = (12 ft)×tan(59°)
Area
The area of the right triangle is given by ...
A = 1/2bh
A = 1/2(12 ft)(12·tan(59°))
Volume
The volume of the prism is the product of its base area and its depth. There are 12 inches in a foot, so a depth of 8 inches is 8/12 of a foot.
V = Bh
V = (1/2·12·12·tan(59°))·(8/12) . . . . cubic feet
V ≈ 79.9 . . . . . cubic feet
You will need 79.9 cubic feet of concrete for the patio.
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Additional comment
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