1)

PQR is a triangular park with PQ=PR=200 m. A TV tower stands at the mid-point of QR. If the angles of elevation of the top of the tower at P,Q and R are respectively 45°,30° and 30° ,then the height of the tower (in m) is 


A) 100

B) 50

C) 1003

D) 502

Answer:

Option A

Explanation:

982019576_heigh.JPG

Let height of tower TM be h

In            PMT.tan45o=TMPM

           1=hPM

     PM=h

In TQM,tan30o=hQM2

   QM=3h

In PMQ   PM2+QM2=PQ2

                               h2+(3h)2=2002

    4h2=(200)2

   h=100 m