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How to find the sides and angle of these two problems

How to find the sides and angle of these two problems-example-1
How to find the sides and angle of these two problems-example-1
How to find the sides and angle of these two problems-example-2
User NeaGaze
by
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1 Answer

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Answer:

See step-by-step explanation.

Explanation:

Part 1: Use the law of cosines to find the measure of angle B:

Law of cosines: c^2 = a2 + b2 โˆ’ 2ab cos(C)

In this case, you're finding b, so b is basically c.

b^2 = a2 + c2 โˆ’ 2ab cos(b)

b=21 a=22 c=16 (just for now)

21^2 = 22^2+16^2- 2(22)(16) cos (b)

441= 484 + 256 - 704 cos(b)

Measure of angle B= 64.8673

Part 2: Use the law of sines to find the measure of angle C


(a)/(sin (A)) =
(b)/(sin (B))=
(c)/(sin(C))

Using angle b and sides b and c: 43.6121

21/ sin ( 64.8673) = 16/ sin(C)

Measure of angle C = 43.6121

Part 3: Find the measure of angle A

1. The angles in a triangle add up 180.

m<A+m<B+m<C=180

m<A+64.8673 + 43.6121 =180

Measure of angle A=71.5206

Page 2

Part 1: Find the measure of angle B

The angles in a triangle add up 180.

m<A+m<B+m<C=180.

42+ m<B+83=180

Measure of angle B= 55 degrees

Part 2: Use the law of sines to find the length of side a


(a)/(sin (A)) =
(b)/(sin (B))=
(c)/(sin(C))

Length of side a =
(b sin(A))/(sin (B)) =
(175 sin(42))/(sin (55))

The length of side a: 142.95

Part 3: Use any method to find the length of side c.

Method= brainpower

aka law of sines:


c=(a sin (C))/(sin A) =
(142.95sin(83))/(sin(42))

c= 212.043

The length of side c: 212.043

User Himadri
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