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Need help! Law of cosines...find b round to the nearest tenth please

Need help! Law of cosines...find b round to the nearest tenth please-example-1

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ANSWER


B = 27.8 \degree

Step-by-step explanation

The law of cosine is given by the formula:


{b}^(2) = {a}^(2) + {c}^(2) - 2bc \cos(B)

From the diagram,

a=17, b=8, c=16

We substitute the given values into the formula to obtain:


{8}^(2) = {17}^(2) + {16}^(2) - 2(17)(16)\cos(B)


64 = 289+ 256- 544\cos(B)



64 = 545- 544\cos(B)



64 - 545 = - 544\cos(B)


- 481 = - 544\cos(B)


( - 481)/( - 544) = \cos(B)


cos(B) = 0.88419


B = \cos ^( - 1) (0.88419)


B = 27.8 \degree
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