Chapter 12

# Shaping Up with Geometry

In This Chapter

Finding the area of a triangle

Using the Pythagorean theorem

Finding the area and circumference of a circle

Calculating the volume of a variety of solids

Geometry is the study of shapes and figures, and it's really popular with the Ancient Greeks, architects, engineers, carpenters, robot designers, and high school math teachers.

A shape is any closed two-dimensional (2-D) geometric figure that has an inside and an outside, and a solid is just like a shape, only it's three-dimensional (in 3-D). In this chapter, you work with three important shapes: quadrilaterals, triangles, and circles. I show you how to find the area and in some cases the perimeter (the length of the edge) of these shapes. I also focus on a variety of solids, showing you how to find the volume of each.

## Getting in Shape: Polygon (And Non-Polygon) Basics

You can divide shapes into two basic types: polygons and non-polygons. A polygon has ...

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