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Find AD. - Mathematics

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Question

Find AD.

Sum

Solution

In ΔABC, 

∠ACD = ∠ABC + ∠BAC

And ∠ABC = ∠BAC   ...(∵ AC = BC)

∴ ∠ABC = ∠BAC

= `48^circ/2`

= 24°

Now,

`(AD)/(AB) = sin 24^circ`

`=>` AD = 30 × 0.4067

= 12.20 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 (C) [Page 342]

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Selina Mathematics [English] Class 10 ICSE
Chapter 22 Height and Distances
Exercise 22 (C) | Q 1.2 | Page 342

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