Researchers use graphs in virtually every area of science and math. We can often gain more insight by studying the graph of an event than by studying the event itself. Solutions to questions that become lost in volumes of data can become quiet clear when the data are plotted on a graph.

For example, in driver’s education, you learn about the appropriate "safe" distance you need to stay behind other vehicles so there is enough time to stop. Below is a chart that displays your speed, thinking distance (how far the car travels from the time you decide to brake until you actually brake), braking distance (how far the car travels until it stops) and the total stopping distance.

I think you will agree that it is much easier to see and interpret the data in the graph than in the chart.

• Use the following terms in a written paragraph to describe the key concepts of this unit.
  • coordinate plane
  • domain
  • function
  • graph
  • inverse of a relation
  • linear equation
  • mapping
  • ordered pair
  • origin
  • quadrant
  • range
  • relation
  • x-axis
  • y-axis
  • x-coordinate
  • y-coordinate
• Graph ordered pairs on a coordinate plane.
• Identify the domain, range, and inverse of a relation.
• Solve linear equations for a variable and a domain.
• Graph linear equations on a coordinate plane.
• Determine if a relation is a function.
• Calculate values for a function.
• Graph inequalities on a coordinate plane.
• Write an equation to represent a relation given a chart of values.