Q. 293.6( 10 Votes )

# From a point on the ground, the angle of elevation of the top of a tower is observed to be 60°. From a point 40m vertically above the first point of observation, the angle of elevation of the top of the tower is 30°. Find the height of the tower and its horizontal distance from the point of observation.

Answer :

The diagram represents the above problem, with PQ as tower and X any Y as points.

In △XQP

Also, XY = 40 m implies RP = 40 m

QR + RP = QP

QR = QP - RP = (QP - 40) m

In △QYR

IMPLIES

[FROM 2 AND YR = XP]

XP = 20(1.73) = 34.6 m

i.e. distance of tower from the point X is 34.6 m

and

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