Q.If the angles of depression from a lighthouse to two ships located along the same straight line are 60° and 30°, and the nearer ship is 150 meters away from the lighthouse, then what is the distance of the farther ship from the lighthouse?

Let AB be the lighthouse, and from point A at the top of the lighthouse, the angles of depression to the masts of two ships located along the same straight line are 60° and 30°, at points C and D respectively. So, ∠EAC = 60° and ∠EAD = 30° (assuming AE || BD) Given: BC = distance to the nearer ship = 150 meters ∠ADB = ∠EAD = 30° and ∠ACB = ∠EAC = 60° From right-angled triangle △ABC: \[ \tan 60^\circ = \frac{AB}{BC} = \frac{AB}{150} \Rightarrow \sqrt{3} = \frac{AB}{150} \Rightarrow AB = 150\sqrt{3} \] From right-angled triangle △ABD: \[ \tan 30^\circ = \frac{AB}{BD} = \frac{150\sqrt{3}}{BD} \Rightarrow \frac{1}{\sqrt{3}} = \frac{150\sqrt{3}}{BD} \Rightarrow BD = 150\sqrt{3} \times \sqrt{3} = 450 \] ✅ Therefore, the farther ship is **450 meters** away from the lighthouse, and the height of the lighthouse is **150√3 meters**.
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