Question

From a point on ground which is 120 m away from the foot of unfinished tower the angle of elevation of the top of the tower is found to bec30° .find how much height of tower have to increase so that it's angle of elevation at same point become 60°

Answer 1

Answer:

80 √3

hope it helps you❣️

Answer 2

Let total height of tower be h.

let DB = n

AD = h - n

now,

In triangle ACB

tan 60 degree = P/B

√3/1 = h/120

h = 120√3

now,

In triangle DCB

tan 30 degree = P/B

1/√3 = x/120

120 = √3x

120/√3 = x

x = 120/√3*√3/√3

x = 120√3/3

x = 40√3

AD = h - n

120√3 - 40√3

80√3

Height of the tower is = 80*1.732

= 138.56m answer