Answer:
82.8 degrees.
Step-by-step explanation:
The largest angle is opposite the longest side.
So we find the angle opposite the 6cm line using The Cosine Rule:
6^2 = 4^2 + 5^2 - 2.4.5 cos A
cos A = (6^2 - 4^2 - 5^2) / (-2*4*5)
= -5/ -40
= 0.125.
So m angle A = 82.819 degrees.
