Question

Law of cosine. Please help

Answer 1

B) 41.7

Explanation:

Let
`a=25`,
`b=32`, and
`c=37`. Use the Law of Cosines equation to find angle A=x which is directly across from side
`a`:

`\displaystyle \cos(A)=(b^2+c^2-a^2)/(2bc)\\ \\\cos(A)=(32^2+37^2-25^2)/(2(32)(37))\\ \\\cos(A)=(1024+1369-625)/(2(1184))\\\\\cos(A)=(2393-625)/(2368)\\ \\\cos(A)=(1768)/(2368)\\\\A=\cos^(-1)\biggr((1768)/(2368)\biggr)\\ \\A\approx41.7^\circ`

Therefore, the correct answer is option B, which means you were right!