1. what are the end points of the triangle called? how are they labeled? 2. two triangles are congruent if: a) each pair of corresponding sides is congruent b) two pairs of corresponding angles are congruent and a pair of corresponding sides are congruent c) two pairs of corresponding sides and the angles included between them are congruent d) if three sides of one triangle are congruent to three sides of a second triangle, e) if two angles and a non-included sides of each triangle are congruent