Properties of Squares and Rectangles

Rectangles

A rectangle is a 4-sided polygon (quadrilateral) with specific rules:

1. Opposite sides are equal in length ($AB = CD$ and $BC = DA$).
2. All angles are equal to $90^\circ$ (Right angles).

Squares

A square is a special type of rectangle.

1. All 4 sides are equal ($AB = BC = CD = DA$).
2. All angles are $90^\circ$.

Naming Convention

When naming a shape like a square or rectangle, you must list the corners in order as you travel around the boundary (either clockwise or counter-clockwise).

• Valid: $PQRS$, $QRSP$, $RSPQ$, $SPQR$.
• Invalid: $PRSQ$ (crossing diagonally).

Rotated Figures

If you rotate a square, it remains a square. The properties (equal sides, right angles) do not change just because the orientation changes.