Let a 5 b 7 and C 42 Solve the triangle Round lengths to

Let a = 5, b = 7, and C = 42. Solve the triangle. Round lengths to the nearest tenth and angles to the nearest whole number. Show all work please.

Solution

a=5,b,7,C=42

using cosine law which is

c^2=a^2 + b^2 -2abcos C

c^2= 5^2 + 7^2 -2(5)(7)cos 42

c^2=74-70cos42

c=4.7

SinC/c=SinB/b

sinB=7sin42/4.7

B=85

A=180-(B+C)=53 degree