Parallelograms (basic properties)

Front

What is a parallelogram?

Back

A parallelogram is a four-sided figure (quadrilateral) where opposite sides are parallel and equal in length.

Front

What are the properties of a parallelogram?

Back

1. Opposite sides are equal in length. 2. Opposite angles are equal. 3. The diagonals bisect each other.

Front

What is the sum of the interior angles of a parallelogram?

Back

The sum of the interior angles of a parallelogram is 360°.

Front

If one angle of a parallelogram is 70°, what are the measures of the other angles?

Back

The opposite angle is also 70°, and the adjacent angles are 110° each.

Front

What does it mean for diagonals to bisect each other in a parallelogram?

Back

It means that each diagonal divides the other into two equal parts.

Front

Are the diagonals of a parallelogram congruent?

Back

No, the diagonals of a parallelogram are not necessarily congruent; they bisect each other.

Front

What is the relationship between opposite angles in a parallelogram?

Back

Opposite angles in a parallelogram are congruent (equal in measure).

Front

What is the relationship between consecutive angles in a parallelogram?

Back

Consecutive angles in a parallelogram are supplementary (they add up to 180°).

Front

If the lengths of two adjacent sides of a parallelogram are 5 cm and 12 cm, what is the perimeter?

Back

The perimeter is 2(5 cm + 12 cm) = 34 cm.

Front

Solve for x: In a parallelogram, if one angle is (3x + 10)° and the adjacent angle is (2x + 20)°, what is x?

Back

x = 10.