Unit A: Geometry

Chapter 1: Polygons

Summary

Quadrilaterals

All quadrilaterals have four properties:

• They all have four sides.
• The sides join to form a closed shape.
• The interior angles add up to 360°.
• The four corners lie flat on the same plane.

Sum of the Angles in a Quadrilateral

• The sum of the angles in a quadrilateral is 360°.
• $\angle A+\angle B+\angle C+\angle D=360°$

Special Quadrilaterals

Each special quadrilateral has unique properties that separate it from the other quadrilaterals.

• kite
• parallelogram
• rectangle
• rhombus
• square
• trapezoid