Question

A window in a building is at a height of 10 m from the ground. The angle
of depression of a point P on the ground from the window is 30°. The angle of
elevation of the top of a building from the point P is 60. Find the height of the
building
(CBSE 2007]​

Answer 1

Answer:

the height of the building is :-

= 30 m .

more information is in attachment ..

Answer 2

Answer :

Height of the building is 30 m.

Step by step explanation :

Let the height of the building be RS

and the window be Q.

Let the base SP = x and RQ = y.

From the Figure :

In ∆PQS

$\sf\tan30\degree=\dfrac{10}{x}$

$\sf\dfrac{1}{\sqrt{3}}=\dfrac{10}{x}$

$\sf\:x=10\sqrt{3}$

Now In ∆SPR

$\sf\tan60\degree=\dfrac{SR}{x}$

$\sf\sqrt{3}=\dfrac{10+y}{10\sqrt{3}}$

$\sf30=10+y$

$\sf\:y=20$

Height of the building

= length of SP

= SQ+QR

=10+y

=30m

Therefore, the height of buliding is 30m.