Identify all the quadrilaterals that have(a) four sides of equal length. (b) four right angles

To identify the quadrilaterals based on the given criteria, let's explore each part.

(a) Four sides of equal length

1. Definition: A quadrilateral with four sides of equal length is called a rhombus.
2. Characteristics:
   • A rhombus has all sides congruent (equal in length).
   • The opposite angles are equal, and adjacent angles are supplementary.
   • The diagonals bisect each other at right angles.

(b) Four right angles

1. Definition: A quadrilateral with four right angles is called a rectangle.
2. Characteristics:
   • A rectangle has opposite sides that are equal in length, and all angles are $90^\circ$.
   • A special case of a rectangle is the square, which has both equal sides and right angles.

Summary

1. Quadrilaterals with four sides of equal length: Rhombus
2. Quadrilaterals with four right angles: Rectangle (and a special case, Square)

These classifications help in understanding the properties and the relationships between different types of quadrilaterals.