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IXL RELATED PLEASE HELP

In ΔDEF, the measure of ∠F=90°, DE = 82 feet, and EF = 55 feet. Find the measure of ∠E to the nearest tenth of a degree.

User Axunic
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1 Answer

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Answer:

To the nearest tenth of a degree

∠E= 47.9°

Explanation:

ΔDEF , let's recognize that it's a right angle triangle because of the presence of ∠F=90°.

Other important measurements are

DE = 82 feet, and EF = 55 feet.

We are to find ∠E

Let's find the missing side first

Side DF

DF² = DE² - EF²

DF²= 82²_55²

DF²=6724-3025

DF²= 3699

DF= 60.82 feet

Let's use the sine formula to look for the angle.

DF/sin ∠E= DE/sin 90

Sin 90= 1

DE= 82

DF= 60.82

Sin ∠E= DF/DE

Sin ∠E= 60.82/82

Sin ∠E= 0.7417

∠E= sin^-1 (0.7417)

∠E= 47.8764

To the nearest tenth of a degree

= 47.9°

User Modesty
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