A statue, 1.6 m tall, stands on the top of a pedestal. From a point on the ground, the angle of elevation of the top of the statue is 60° and from the same point the angle of elevation of the top of the pedestal is 45°. Find the height of the pedestal.
Let height of the pedestal BD be h metres, and angle of elevation of C and D at a point A on the ground be 60° and 45° respectively.It is also given that the height of the statue CD be 1.6 mi.e., ∠CAB = 60°,∠DAB = 45° and CD = 1.6mIn right triangle ABD, we have In right triangle ABC, we have Comparing (i) and (ii), we get Hence, the height of pedestal Let A and B the position of the first ship and the second ship Distance = `200((sqrt(3) + 1)/sqrt(3))`m Let the height of the lighthouse CD be h In the right ∆ACD, tan 60° = `"CD"/"AD"` `sqrt(3) = "h"/"AD"` ∴ AD = `"h"/sqrt(3` ...(1) In the right ∆BCD tan 45° = `"DC"/"BD"` 1 = `"h"/"BD"` ∴ BD = h Distance between the two ships = AD + BD `200((sqrt(3) + 1)/sqrt3) = "h"/sqrt3 + "h"` ⇒ `200 (sqrt(3) + 1) = "h" + sqrt(3)"h"` `200(sqrt(3) + 1) = "h"(1 + sqrt(3))` ⇒ h = `(200(sqrt(3) + 1))/((1 + sqrt(3))` h = 200 Height of the light house = 200 m |