Answer:
11.5 m
Step-by-step explanation:
The problem can be solved using a trig relation that relates the side opposite the angle to the side adjacent to the angle. That relation is ...
Tan = Opposite/Adjacent
The lengths of the adjacent sides of the triangle can be found by rearranging this formula:
Adjacent = Opposite/Tan
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The "opposite" side of the triangle is the height of the tree, which we can represent using h. The problem statement tells us of a relation between adjacent side lengths and angles:
h/tan(25°) -h/tan(50°) = 15 . . . . . moving 15 meters changes the angle
h(1/tan(25°) -1/tan(50°)) = 15
h = 15·tan(25°)·tan(50°)/(tan(50°) -tan(25°)) = 15(0.55572/0.72545)
h ≈ 11.4907 . . . . meters
The height of the tree is about 11.5 meters.