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In DEF, FE=13 and m(angle)F=34. Find DF to the nearest tenth

In DEF, FE=13 and m(angle)F=34. Find DF to the nearest tenth-example-1
User Bniwredyc
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2 Answers

2 votes
A.15.7
is the answer because fe is 13

User Michalmuskala
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3 votes

Answer:

DF is 15.7 unit

Explanation:

Given,

In triangle DEF,

m∠E = 90°, m∠F = 34° and EF = 13,

We have to find the measure of side DF.

By the property of a triangle,

m∠E + m∠F + m∠D = 180°

⇒ 90° + 34° + m∠D = 180°

m∠D = 180° - 124° = 56°

By the law of sines,


(sin D)/(EF)=(sin E)/(DF)


sin D* DF = sin E* EF ( By cross multiplication )


\implies DF = ( sin E* EF)/(sin D)

By substituting values,


DF = (sin 90^(\circ)* 13)/(sin 56^(\circ))=15.6808333306\approx 15.7\text{ unit}

User Kazim Homayee
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