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The sun casts a 70 foot shadow on a 30 foot tree. Find the angle of elevation to the nearest degree.

User Arikfr
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1 Answer

5 votes

Answer:

23°

Explanation:

We apply Pythagorean theorem to determine the missing length, Hypotenuse:


h^2+b^2=H^2\\\\70^2+30^2=H^2\\\\H=√(5800)\\\\=76.15773\ ft

This hypotenuse corresponds to the right triangle and the tree's height, corresponds to the angle of elevation:

-We apply the law of Sines;


(a)/(Sin \ A)=(b)/(Sin\ B)\\\\\\(76.15773)/(Sin \ 90)=(30)/(Sin\ h)\\\\h=Sin^(-1)(30)/(76.15773)\\\\=23.19859\approx 23\textdegree

Hence, the angle of elevation is 23°

User Atif Majeed
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