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I’m having trouble understanding how to solve this someone please help ASAP thank you!

Use the Law of Cosines to solve the problem. You must solve for BC first. Solve this problem in order.

A ship travels due west for 94 miles. It then travels in a northwest direction for 119 miles and ends up 173 miles from its original position. To the nearest tenth of a degree, how many degrees north of west (x) did it

turn when it changed direction? Show your work.

I’m having trouble understanding how to solve this someone please help ASAP thank-example-1
User Krizzo
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1 Answer

16 votes
16 votes

Answer:

Answer is 71.95°

Explanation:

Cosine formula is

a^2=b^2+c^2-2bc(cosA)

cos A =b^2+c^2-a^2/2bc

if a= 119,b=94,c=173

cos A=94^2+173^2-119^2/2(94*173)

=8836+29,929-14,161/2(16,262)

=38765-14,161/32,524

=24604/32,524

=0.7564

cos A=0.7564

cos^-1=40.85°.that's for angle A.

Using the same formula

B=31.1°

C=180-(40.85+31.1)

C=180-71.95

C=108.05

Since angle on a straight line is 180

therefore x is 71.95

Also the sum of angles A and B

User Wid
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