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From the figure, given below, calculate the length of CD. - Mathematics

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Question

From the figure, given below, calculate the length of CD.

Sum

Solution

In right ΔACB, we have

tanθ=ABBC

tan47=AB15

1.0724=AB15

∴ AB = 1.0724 × 15

= 16.0860 m

= 16.09 m.

And in right ΔADE, we have

tan22=AEDE

0.4040=AE15

∴ AE = 15 × 0.4040

= 6.0600

= 6.06 m.

∴ CD = EB

= AB – AE

= 16.09 – 6.06

= 10.03 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 (B) [Page 341]

APPEARS IN

Selina Mathematics [English] Class 10 ICSE
Chapter 22 Height and Distances
Exercise 22 (B) | Q 6 | Page 341

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