Question

If one pair of opposite sides of a quadrilateral is both congruent and __________, then the quadrilateral is a parallelogram.

A) perpendicular

B) parallel

C) increasing

D) decreasing

Answer 1

B) Parallel

Explanation:

For the opposite angles of the parallelogram to be equal, the sides making up the angles must be parallel to maintain this angle.

Answer 2

B) parallel

Explanation:

If one pair of opposite sides of a quadrilateral is both congruent and parallel, then the quadrilateral is a parallelogram. This is because a parallelogram is defined as a quadrilateral with two pairs of parallel sides.

The other options are not correct:

• A) perpendicular: A parallelogram does not have to have perpendicular sides.
• C) increasing: A parallelogram does not have to have increasing sides.
• D) decreasing: A parallelogram does not have to have decreasing sides.

Note:

The opposite sides of the parallelogram are both congruent and parallel.