Properties of Parallelograms

Front

What is a parallelogram?

Back

A parallelogram is a quadrilateral with opposite sides that are both parallel and equal in length.

Front

What theorem shows that a quadrilateral is a parallelogram?

Back

If the diagonals of a quadrilateral bisect each other, then the quadrilateral is a parallelogram.

Front

What is the property of opposite sides in a parallelogram?

Back

In a parallelogram, opposite sides are congruent (equal in length).

Front

What is the property of opposite angles in a parallelogram?

Back

In a parallelogram, opposite angles are congruent (equal in measure).

Front

What is the property of consecutive angles in a parallelogram?

Back

In a parallelogram, consecutive angles are supplementary (their measures add up to 180 degrees).

Front

What can be concluded if both pairs of opposite sides of a quadrilateral are congruent?

Back

If both pairs of opposite sides are congruent, then the quadrilateral is a parallelogram.

Front

What can be concluded if both pairs of opposite angles of a quadrilateral are congruent?

Back

If both pairs of opposite angles are congruent, then the quadrilateral is a parallelogram.

Front

What can be concluded if the diagonals of a quadrilateral bisect each other?

Back

If the diagonals bisect each other, then the quadrilateral is a parallelogram.

Front

What is the relationship between the diagonals of a parallelogram?

Back

The diagonals of a parallelogram bisect each other.

Front

If one pair of opposite sides of a quadrilateral is both parallel and congruent, what can be concluded?

Back

The quadrilateral is a parallelogram.