Heather must prove this theorem: If a quadrilateral is a parallelogram, then the opposite sides are congruent.
8
theorem. ABCD. and
Below is her paragraph proof of the theorem.
By definition the opposite sides of a parallelogram are parallel. 21 and 2223 because alternate interior angles are congruent. AA BC 2 ACDA by the
BC DA by CPCTC
Which choice correctly fills in the blank line in the paragraph prool?
O SAS
O SSS
O CPCTC
O ASA