+4 Two of the exterior angles of a triangle are 158 degrees and 99 degrees Find the third exterior angle, in degrees.
+80 Alright. So we know that the interior angles of a triangle add up to 180 degrees, so we find the interior angles of each angle by subtracting the exterior angle from 180.
\(1: 180-158=22\)
\(2:180-99=81\)
Therefore, 22+81+c(the third angle) must be 180.
103+c=180
\(\fbox{c=77}\)
