Question
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.
Solution
Let AB be the tower with height h.
Let x be the angle of elevation from c.
So, the angle of elevation from D is (90-x).
..........( Since the angle of elevation from C and D are complementary)