Representing Integers on a Number Line
A number line is used to represent the set of integers. Positive integers are represented to the right side of zero and negative integers are to the left side of zero on a number line. -1, -2, -3, etc., are the respective opposites (or additive inverses) of 1, 2, 3, etc. A pair of opposite integers are on either side of zero and at the same distance from zero. The sum of a pair of opposite integers is zero.
Points to remember:
- The number line goes on forever in both directions. This is indicated by the arrows.
- Whole numbers greater than zero are called positive integers. These numbers are to the right of zero on the number line.
- Whole numbers less than zero are called negative integers. These numbers are to the left of zero on the number line.
- The integer zero is neutral. It is neither positive nor negative.
- The sign of an integer is either positive (+) or negative (-), except zero, which has no sign.
- A positive integer does not have to have a + sign in it. For example, +9 and 9 are interchangeable.
- Two integers are opposites if they are each the same distance away from zero, but on opposite sides of the number line. One will have a positive sign, the other a negative sign. In the number line above, +4 and -4 are called as opposites.
Directions: Choose the correct answers for the following questions. Also write at least five examples of your own and show the number line for each question.