Common Core: High School - Geometry

Explore the principles and applications of geometry, including shapes, theorems, and real-world problem-solving.

Basic Concepts

Quadrilaterals and Polygons

Exploring Polygons

Polygons are closed shapes with straight sides. Quadrilaterals are polygons with four sides, but polygons can have any number of sides.

Types of Quadrilaterals

  • Rectangle: Opposite sides equal; angles are 90°.
  • Square: All sides and angles equal.
  • Parallelogram: Opposite sides are parallel and equal.
  • Trapezoid: Only one pair of sides is parallel.

Properties of Polygons

  • The sum of interior angles of an \(n\)-sided polygon is \((n-2) \times 180^\circ\).
  • Polygons are found everywhere, from honeycombs (hexagons) to stop signs (octagons)!

Why Study Polygons?

Polygons help us understand tiling, art, architecture, and even computer graphics for games and animation.

Examples

  • A soccer field is shaped like a rectangle.

  • Windows often have a square or rectangular design.

In a Nutshell

Polygons, especially quadrilaterals, are key to understanding many real-world shapes and structures.