Question

Select the angle that correctly completes the law of cosines for this triangle

Answer 1

c 28^o

Explanation:

Answer 2

Final answer is C. 28°.

Explanation:

Given equation is
`15^2+17^2-2\left(15\right)\left(17\right)\cos\left(\theta \right)=8^2`.

Now we need to find the missing value of
`\theta` using cosine formula. So let's compare the given equation
`15^2+17^2-2\left(15\right)\left(17\right)\cos\left(\theta \right)=8^2` with cosine formula
`b^2+c^2-2\left(b\right)\left(c\right)\cos\left(A\right)=a^2`.

we get
`\theta =A`

which is basically the angle between given sides 15 and 17

Hence A=28°.

So the final answer is 28°.