Answer:
x=140°
Explanation:
to get the exterior angle add the 2 given sides 72 and 68 to find the last interior angle
72°+68°=140°
all sums of interior angles should equal 180° so
180°-140=40°
take 40° and subtract is by 180°
180°-40°=140°
(A flat line is 180°)
so x=140°