Question

In triangle LMN, LM = 6, MN = 9, and LN = 7. Find m∠M to the nearest tenth of a degree. A. 50.0 degrees B. 41.8 degrees C. 45.5 degrees D. 87.3 degrees Please help I need it as soon as possible! Thank you

Answer 1

A. 50.0 degrees

Explanation:

In a triangle LMN, we are given te following;

LM = 6

MN = 9

LN = 7

To get the angle m<M, we will use the cosine rule

LN² = LM²+MN² - 2(LM)(MN)cosm<M

7² = 6²+9²-2(6)(9)cosm<M

49 = 36+81-108cosm<M

49 = 117-108cosm<M

49 - 117 = -108cosm<M

-68 = -108cosm<M

cosm<M = -68/-108

cosm<M = 17/27

cosm<M = 0.6296

m<M = cos^-1(0.6296)

m<M = 50.97

Hence the required angle to nearest tenth is 50.0 degrees