Concept Byte: Graphs in Three Dimensions

For Use With Lesson 3-5

ACTIVITY

To describe positions in space, you need a three-dimensional coordinate system. You have learned to graph on an xy-coordinate plane using ordered pairs. Adding a third axis, the z-axis, to the xy-coordinate plane creates coordinate space. In coordinate space you graph points using ordered triples of the form (x, y, z).

	Image Long Description
A two-dimensional coordinate system allows you to graph points in a plane.	A three-dimensional coordinate system allows you to graph points in space.

In the coordinate plane, point (2, 3) is two units right and three units up from the origin. In coordinate space, point (2, 3, 4) is two units forward, three units right, and four units up.

Activity 1

Define one corner of your classroom as the origin of a three-dimensional coordinate system like the classroom shown. Write the coordinates of each item in your coordinate system.

1. each corner of your classroom
2. each corner of your desk
3. one corner of the blackboard
4. the clock
5. the waste-paper basket
6. Pick 3 items in your classroom and write the coordinates of each.

Table of Contents