in triangle PQR, PQ=5.4, QR=3.6, and PR=6.2. to the nearest tenth, what is m<R?

Answer 1

cosine law ....

5.4^2 = 6.2^2 + 3.6^2 - 2(6.2)(3.6)cosR
cosR = 22.24/44.64
= .4982..

R = 60.1°