Chapter 12.2B, Problem 21A

To determine

(a)

To find:

The opposite angles of parallelogram are congruent i.e., $\angle A\cong \angle C$ and $\angle B\cong \angle D$

To determine

(b)

To find:

$\overline{BC}\cong \overline{AD}$ and $\overline{AB}\cong \overline{CD}$ i.e., opposite sides of parallelogram are congruent.

To determine

(c)

To find:

Diagonal of parallelogram bisect each other $\overline{BF}\cong \overline{DF}$ and $\overline{AF}\cong \overline{CF}$.

To determine

(d)

To find:

$\angle DAB$ and $\angle ABC$ are supplementary.