A ladder leans against the side of a house. The angle of elevation of the ladder is 66°, and the top of the ladder is 13 ft above the ground. Find the distance from the bottom of the ladder to the side of the house.
This is a simple application of trigonometry. The angle of elevation is the non-right angle touching the ground. We can call that angle theta. We already have the opposite side and we need the adjacent side. We can use tangent function to find it. Because tan 66 degrees = O/A, we can substitute to get 2.246 = 13/A. Divide 13 by 2.246 and you'll get 5.788 ft.
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