ANSWERS
a. Yes, congruent. By SSS postulate
b. Yes, congruent. By AAA postulate
c. Yes, conguent. By SAS postulate
EXPLANATION
a. Sides MQ and MN are congruent as shown in the diagram. So are sides PN and PQ. Side PM is shared by both triangles so it must be congruent to both.
b. It is shown in the diagram which angles are congruent:
c. Angles DEC and AEB are <em>vertical angles</em> and they are therefore congruent. The two sides that form those angles are shown congruent in the diagram, so we have a side, the next angle and the next side: SAS postulate.
