The figure shows parallelogram ABCD with diagonal AC. Complete the two column proof to prove that opposite angles ABC and CDA are congruent.
Statements
Quadrilateral ABCD is a parallelogram
Reasons
Given
Opposite sides of a parallelogram are congruent
AB | CD
Alternate interior angles are congruent
Reflexive Property
AC AC
ABAC =ADCA
Corresponding parts of congruent triangles are congruent
ZBCA ZDAC
ZBAC DCA
ZABC ZCDA
ABCD
BC DA
SAS
SSS
AAS
Definition of a parallelogram
Definition of a quadrilateral