Question

A, B, C and D are on horizontal level ground and CT is vertical pole. B is 35 m due east of C, A is 60 m South of C and D is 60 m West of A.

Calculate the angle of elevation of T from N.

I m really suck...plz help

Answer 1

beats me -- where is N?

Answer 2

From Pyth thereom,AB =root (35^2+60^2)= 5 root(193)

Height CN=AC*CB/ AB= 60*35/ 5 root(193)= 420/root(193)

Now find CT
Tan40 = CT/ DC
But DC= 60 root 2 ( it is hyp of rt triangle ADC)

CT= DC tan 40= 60 root 2 * 0.84

Angle of elevation of TN is

Arc Tan(CT/CN)= Arc tan (60 root 2 * 0.84/420/root(193))

= Arc tan ( root 386 * 0.12)
= Arc tan ( 19.65 * 0.12)
= Arc tan (2.358)
= 67.02 deg