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The upper part of a tree, broken over by the wind, makes an angle of 45° with the ground and the distance from the root to the point where the top of the tree touches the ground is 15 m. - Mathematics

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Question

The upper part of a tree, broken over by the wind, makes an angle of 45° with the ground and the distance from the root to the point where the top of the tree touches the ground is 15 m. What was the height of the tree before it was broken?

Sum

Solution

Let the height of the tree after bracking be h m

Here θ = 45°

tan45=h15

1=h15

∴ h = 15 m

Now, length of the tree broken by the wind

= 15sin45

= 152

= 21.21 m

So, height of the tree before it was broken is (15 + 21.21) m = 36.21 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: Height and Distances - Exercise 22 (A) [Page 337]

APPEARS IN

Selina Mathematics [English] Class 10 ICSE
Chapter 22 Height and Distances
Exercise 22 (A) | Q 7 | Page 337

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