Answer:
See attachment
Explanation:
If x + y = 180°, the remaining angles can be labelled as illustrated in the diagram provided in the attachment below.
To properly label the diagram so that x° + y° = 180°, you must bear in mind or recall relation between angles formed when two parallel lines are cut across by a transversal line.
x° would be congruent to any angle that is either corresponding or vertical to it.
That is, for the angles labelled x°, such an angle is either corresponding to the given x° or it is vertically opposite to it.
Consequently, where the angle labelled y° forms a linear pair with x°. Linear pair of angles add up to give 180°.