A quadrilateral has: 1. four sides (edges) 2. four vertices (corners) 3. interior angles that add to 360 degrees: Try drawing a quadrilateral, and measure the angles. They shoul… See more

There are special types of quadrilateral: Some types are also included in the definition of other … See more

the little squares in each corner mean "right angle" A rectangle is a four-sided shape where every angle is a right angle(90°). Also opposite sides are paralleland of equal length.… See more

the little squares in each corner mean "right angle" A squarehas equal sides (marked "s") and every angle is a right angle (90°) Also opposite sides are parallel. A square also fits th… See more