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The Angles of Elevation of the Top of a Tower from Two Points at a Distance of 4 M and 9 M from the Base of the Tower and in the Same Straight Line with It Are 60° and 30° Respectively. Find the Height of the Tower. - Mathematics

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प्रश्न

The angles of elevation of the top of a tower from two points at a distance of 4 m and 9 m from the base of the tower and in the same straight line with it are 60° and 30° respectively. Find the height of the tower.

उत्तर

Let the height of the tower be h m.

 In ABP,

`tan60^@ = h/4`

`=>sqrt3=h/4`

h=1.73×4=6.92 cm

In ABQ

`tan30^@=h/9`

`=>1/sqrt3=h/9`

`=>h=9/sqrt3cm= 5.20 cm`

Using the given data, we are getting two different values of h, which is not possible.

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2015-2016 (March) Delhi Set 2

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