Answer:
Choice B.
Step-by-step explanation:
In a parallelogram, there are two pairs of parallel, opposite sides.
In a parallelogram, there are two pairs of congruent, opposite sides.
In a parallelogram, there are two pairs of congruent, opposite angles.
The pairs of opposite congruent angles of this parallelogram are:
<ABC and <ADC
<BCD and <BAD
This problem asks about an angle, but the angle is <BDC.
Notice that <BDC is not one of the 4 angles of the parallelogram mentioned above. <BDC is formed by drawing a diagonal. The statement above about pairs of congruent, opposite angles does not apply to <BDC.
Side DC is parallel to side AB.
Diagonal BD is a transversal to lines DC and AB.
<BDC and <ABD are alternate interior angles of the two parallel sides and the transversal.
Answer:
Choice B.
<BDC is congruent to <ABD; Alternate interior angles are congruent.
