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a math student is standing 40 feet from the base of a water tower. the angle of elevation from her horizontal line of sight is 72 degrees. If her "eye height" is 5 feet, how tall is the water tower? Round to the nearest foot.​

1 Answer

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Answer:

128 ft

Explanation:

The height of the tower above eye-height is related to the angle by ...

Tan = Opposite/Adjacent

tan(72°) = (tower height above eye height)/(40 ft)

tower height above eye height = (40 ft)×tan(72°) = 123 ft

Since eye height is 5 ft, the total height of the tower from the ground is ...

tower height = eye height + height above eye height

tower height = 5 ft + 123 ft

tower height = 128 ft

User Josh Cartwright
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