The angle of depression of a point on the ground as seen from the top of a tower, 65 feet high, is 45°. Find the distance of the point on the ground from the foot of the tower.
Let θ be the angle of depression of the point on the ground as seen from the top of a tower, here θ = 45° Let AC be the height of the tower, here AC = 65 feet. Let the distance of the point on the ground from the foot of the tower, AB = x feet. Here, tan θ = AC/AB ⇒ tan 45° = 65/x ⇒ 1 = 65/x ⇒ x = 65 feet