sir this is the question from the book -ML aggarwal( avichal publication) class 10th , chapter20 , heights and distances

we have the data that :- The angle of elevation of the top of a tower from a point on the ground and at a distance of 150 m from its foot is 300.

Now we have to find theĀ height of the tower correct to one place of decimal.

This is a very important question

question no 2 , heights and distances , ICSE board

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# The angle of elevation of the top of a tower from a point on the ground and at a distance of 150 m from its foot is 300. Find the height of the tower correct to one place of decimal.

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Consider BC as the tower and A as the point on the ground such that

ā A = 30

^{0}Ā and AC = 150 mTake x m as the height of the tower

We know that

tan Īø = BC/AC

Substituting the values

tan 30

^{0}Ā = x/150By cross multiplication

1/ā3 = x/150

So we get

x = 150/ā3

Multiplying and dividing by ā3

x = (150 Ć ā3)/ (ā3 Ć ā3)

By further calculation

x = 150ā3/ 3 = 50ā3 m

Substituting the value of ā3

x = 50 (1.732)

x = 86.600 m

x = 86.6 m