Rectangular Coordinate System - Problem 6

A line on a graph represents the picture of all of the input-output pairs that make a relationship true. Often, we have infinitely many possible inputs with infinitely many outputs, which creates a "ruler straight" line. In the real world, a straight line would represent a continuous variable- something like how much money you would pay for a certain number of pounds of rice: you can buy partial pounds. This is a continuous linear relationship. Contrast that idea with something discrete, or a separate set of points, that look like a line but we actually don't connect them unless we're showing a trend. Consider if avocados cost $1 each- you would buy 1, or 2 or 3 avocados and pay $1 or $2 or $3, but you couldn't really buy partial avocados or pay cents on a dollar. This is a discrete linear relationship.