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5 votes
Please help !

Find a.
Round to the nearest tenth:
27 cm
102
28
a = [? ]cm
Law of Sines: sin A
sin C
sin B
b
a
A=?

Please help ! Find a. Round to the nearest tenth: 27 cm 102 28 a = [? ]cm Law of Sines-example-1

1 Answer

5 votes

Given:

In the given triangle the measure of two angles are 102 degree and 28 degrees and the sides of the triangle are a, 27 cm, c.

To find:

The value of a.

Solution:

Let the given triangle be ABC, such that,


m\angle B=28^\circ


m\angle C=102^\circ


b=27\ cm

Using angle sum property of triangles, we get


m\angle A+m\angle B+m\angle C=180^\circ


m\angle A+28^\circ+102^\circ=180^\circ


m\angle A=180^\circ-28^\circ-102^\circ


m\angle A=50^\circ

According to the Law of Sines:


(\sin A)/(a)=(\sin B)/(b)


(\sin 50^\circ )/(a)=(\sin 28^\circ )/(27)


(27* \sin 50^\circ )/(\sin 28^\circ)=a


(27* \sin 50^\circ )/(\sin 28^\circ)=a


a\approx 44.06

Therefore, the value of a is about 44.06 cm.

User Anthony Anisimov
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