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In △CDE , CD=14 , DE=9 , and m∠E=71∘ .

What is m∠D to the nearest tenth of a degree?

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m∠D = [ ]°

User Ufxmeng
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4.7k points

2 Answers

4 votes

Answer:

71.6°

Explanation:

CD/sinE = DE/sinC

14/sin(71) = 9/sinC

sinC = 0.60783337

C = 37.43300585

Angle D = 180 - 37.43300585 - 71

Angle D = 71.56699415

User Conor Neilson
by
5.6k points
3 votes

Answer:

71.6 degrees

Explanation:

We can use the law of sines:
(a)/(sinA) =(b)/(sinB)=(c)/(sinC)

Here, we have:
(14)/(sin71) =(9)/(sinC)

Solving for C, we have: 14 * sinC = 9 * sin71 ⇒ C = 37.4 degrees

To find angle D, we take 180 degrees and subtract angles E and C from it:

180 - 71 - 37.4 = 71.6 degrees.

Thus, the answer is 71.6 degrees.

Hope this helps!

User Coppermill
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5.4k points