Parallel lines, angle bisector and exterior angle of a triangle

Question:

In the figure below, the angle A is 58^{o} and CD is parallel to AB. CE is an angle bisector which bisects the angle ACD and intesect AB at E.
what is the degree measure of the angle CEB?

Solution:

since AB // CD (Given)

so angle A + angle ACD = 180^{o}

because angle A and angle ACD are interior angles on the same side of the transversal CA, because AB // CD, so these two angles are supplementary