What is a trapezium? When do you call a trapezium an isosceles trapezium?

Draw an isosceles trapezium. Measure its sides and angles.

The diagonals of a parallelogram are equal.

The diagonals of a rectangle are perpendicular to each other.

The diagonals of a rhombus are equal.

Give reasons for the following:

A square can be thought of as a special rectangle.

Give reasons for the following:

A square can be thought of as a special rhombus.

Give reasons for the following:

A rectangle can be thought of as a special parallelogram.

Give reasons for the following:

A square is also a parallelogram.

A figure is said to be regular if its sides are equal in length and angles are equal in measure. What do you mean by a regular quadrilateral?