On a straight line passing through the foot of a tower, two points C and D
Trigonometry (10)On a straight line passing through the foot of a tower, two points C and D are at distances of 4 m and 16 m from the foot respectively. If the angles of elevation from C and D of the top of the tower are complementary, then find the height of the tower.
Answer
$$ \text{tan} $\theta = \frac{h}{4} $$
$$ \text{tan} (90 - \theta) = \frac{h}{16} $$
$$ \text{cot} \theta = \frac{h}{16} $$
Solving (i) and (ii) to get
h2 = 64
h = 8 m
Exam Year:
2017
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