1. Quadrilaterals project Dimera wideman 1/16/13

2. Quadrilateral Quadrilateral just means "four sides" (quad means four, lateral means side). Any four-sided shape is a Quadrilateral. But the sides have to be straight, and it has to be2-dimensional.

3. square A 4-sided flat shape with straight sides where: * all sides have equal length, and * every angle is a right angle (90°) 90

4. Rectangle A rectangle is a four-sided shape where every angle is a right angle (90°). Also opposite sides are parallel and of equal length

5. Trapezoid A trapezoid (called a trapezium in the UK) has a pair of opposite sides parallel. It is called an Isosceles trapezoid if the sides that aren't parallel are equal in length and both angles coming from a parallel side are equal, as shown.

6. Parallelogram A 4-sided flat shape with straight sides where opposite sides are parallel. Also: * opposite sides are equal in length, and * opposite angles are equal (angles "a" are the same, and angles "b" are the same)

7. Rhombus A 4-sided flat shape with straight sides where all sides have equal length. Also opposite sides are parallel and opposite angles are equal. It is a type of parallelogram.