#### Answer

The real number line is a graph used to represent the set of real numbers.

#### Work Step by Step

The real number line is a graph used to represent the set of real numbers. An arbitrary point, called the origin, is labeled 0. Select a point to the right of 0 and label it 1. The distance from 0 to 1 is called the unit distance. Numbers to the right of the origin are the positive and numbers to the left of the origin are the negative.