So we already know that one angle is 38 degrees, so we have that one. The angle, 101 is exterior, and we have to subtract 180 from that to get the interior angle. We get a difference of 79. Since the sum of a triangle's interior angles are 180, we have to add 38+79 to get 117. Then, we have to subtract it from 180 to get the value of the interior angle as 63 degrees. Because x is on the outside, we have to again subtract 63 from 180 to get the missing value of x as 117.
