**Definition of Quadrilateral **

- A quadrilateral is a four-sided polygon.

**Examples of Quadrilateral**

**More about Quadrilaterals**

**Parallelogram:**A quadrilateral with two pairs of opposite sides parallel.**Rhombus:**A parallelogram with four congruent sides.**Rectangle:**A parallelogram with four right angles.**Square:**A parallelogram with four congruent sides and four right angles.**Trapezoid:**A quadrilateral with only one pair of parallel sides.

**Solved Example on Quadrilateral**

A quadrilateral with vertices (0, 0), (5, 0), (8, 4) and (3, 4) forms a ________.

Choices:

A. Rhombus

B. Square

C. Rectangle

D. Trapezoid

Correct Answer: A

Solution:

Step 1:Let (0, 0), (5, 0), (8, 4), and (3, 4) be A, B, C, and D respectively.

Step 2:Use the distance formula,

Step 3:

Step 4:

Step 5:

Step 6:

Step 7:

Step 8:

Step 9:The lengths of the sides AB, BC, CD, and DA are equal and the lengths of the diagonals AC and BD are not equal in quadrilateral ABCD.

Step 10:So, ABCD is a rhombus.

**Related Terms for Quadrilateral**

- Polygon
- Parallelogram
- Rhombus
- Rectangle
- Square
- Trapezoid
- Congruent
- Parallel