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A quadrilateral is a polygon with $4$ sides.

## What are some common types of quadrilaterals?

Some common types of quadrilaterals include squares, rectangles, rhombuses, and trapezoids.

## What is the difference between a square and a rectangle?

A square has four sides that are all the same length, while a rectangle has two sets of two sides that are the same length.
A square is always is a rectangle but a rectangle is not a square.

## What is a right angle?

A right angle is a type of angle that looks like the corner of a square. When two lines meet at a right angle, they form a $90$ degree angle.
One way to tell if an angle is a right angle is to use a tool called a protractor to measure it. Another way is to use a right angle ruler or "square" to see if the two lines line up perfectly with the tool.

## Want to join the conversation?

• How is a rectangle not a square but a square is a rectangle?
• A square is a rectangle because it meets all the criteria of a rectangle: it has four sides, and all its angles are right angles. However, for a square, all its sides are the same length!

Now, a rectangle can have sides of different lengths, as long as the opposite sides are equal. But if all four sides of a rectangle were the same length, then it wouldn't just be a rectangle anymore, it'd also be a square! So, a rectangle can be a square, but only if all its sides are the same length. Otherwise, it's just a rectangle, not a square.
• a right angle is two lines the look like this L
• in a Square there are specifically 4/four right angles. "ha am I right(get it)!
• Why’s a square a rectangle but a rectangle is not a square
• The sides of a square are all the same length. The sides of a rectangle are not always equal in length.
• how is a square a rectangle but a rectangle is not a square
• because that´s the way of life
• what is right angle
• A angle that is 90 degrees
• can we have games on khan Academy