9.1 – Introduction to The Coordinate Plane

What you’ll learn to do: Graph linear equations on the coordinate plane.

The coordinate plane was developed centuries ago (in 1637, to be exact) and refined by the French mathematician René Descartes. In his honor, the system is sometimes called the Cartesian coordinate system. The coordinate plane can be used to plot points and graph lines. This system allows us to describe algebraic relationships in a visual sense, and also helps us create and interpret algebraic concepts.

Specifically, in this section you’ll learn how to:

  • Plot ordered pairs on a rectangular coordinate system
  • Identify quadrants on the coordinate plane
  • Identify points on a graph
  • Determine when an ordered pair is a solution of an equation
  • Complete a table of solutions to a linear equation
  • Graph linear equations using ordered pairs

 

Before you get started in this module, try a few practice problems and review prior concepts.

Readiness Quiz

1)

If you missed this problem, review the example below.

Evaluate [latex]x+7[/latex] when

  1. [latex]x=3[/latex]
  2. [latex]x=12[/latex]

2)

If you missed this problem, review this example.

[latex]\text{Evaluate }3x+4y - 6\text{ when }x=10\text{ and }y=2[/latex].

3)

If you missed this problem, review the following video.