Question

From the top of a 9 metres high building AB, the angle of elevation of the top of a tower CD is 30º and the angle of depression of the foot of the tower is 60º. What is the height of the tower? a) 11 b) 12 c) 13 d) 14

Answer 1

answer is 12 option (b) .Firstly you take traingle ABD and find value of BD by apply tan 60°.we get BD equal to 3√3 .now in traingle AEC we get lenght of CE is 3 unit then add CE+ED we get 12 unit.