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The Angle of Elevation of the Top of a Vertical Cliff from a Point 30 M Away from the Foot of the Cliff is 60°. Find the Height of the Cliff. - Mathematics

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Question

The angle of elevation of the top of a vertical cliff from a point 30 m away from the foot of the cliff is 60°. Find the height of the cliff. 

Sum

Solution

Let AB be the diff and angle of elevation from point C (on ground) is 30 °. 
In ΔABC

`("AB")/("BC") = tan60^circ`

`"AB"/30 = sqrt(3)`

AB = `30sqrt(3)` m

So , height of tower is `30sqrt(3)` m

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Heights and Distances - Solving 2-D Problems Involving Angles of Elevation and Depression Using Trigonometric Tables
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Chapter 22: Heights and Distances - Exercise

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Frank Mathematics - Part 2 [English] Class 10 ICSE
Chapter 22 Heights and Distances
Exercise | Q 2

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