Quadrilaterals are important shapes that help us solve tricky geometry problems. They have special features that make it easier to tackle different challenges. Let’s look at the main types of quadrilaterals and what makes them unique:

1. Parallelograms:

   • Opposite sides are parallel and the same length.
   • Opposite angles are also the same.
   • The diagonals (the lines that connect opposite corners) cut each other in half.

2. Rectangles:

   • They have all the properties of parallelograms.
   • All angles are right angles (that means each is $90^\circ$).
   • The diagonals are the same length.

3. Squares:

   • They have all the features of rectangles and rhombuses.
   • All sides are the same length.
   • The diagonals are equal and cut each other at right angles.

4. Rhombuses:

   • All sides are the same length.
   • Opposite angles are the same.
   • The diagonals cut each other at right angles but are not always the same length.

Key Facts:

• You can find the area of a rectangle using the formula: Area = length × width.
• To find the perimeter (the total distance around) of a square, use the formula: Perimeter = 4 × side length.
• Knowing these properties helps you solve tough problems, like finding unknown heights using the Pythagorean theorem with quadrilaterals.

These qualities help students figure out geometry problems involving angles, area, and perimeter easily.