Find a, b, and c.
180 - 139 =61
c =180 - 61 - 77 = 62
b=180 - 62 = 118
139 - 77 - 36 =26 angle between 77 and 36
a =180 - 118 - 26 = 36
So:a =36, b= 118, c =62, or the LAST one on your list.
