Signed Numbers Study Guide: GED Math

Practice problems for these concepts can be found at:

Numbers and Operations Practice Problems: GED Math

Number Lines and Signed Numbers

A signed number is a number with a positive (+) or a negative (–) sign in front of it. Any number can have a sign in front of it. If a number has no sign in front of it, it is + (positive).

Signed whole numbers (and zero) make up a group of numbers called integers. Integers are often represented on a number line. Zero (0) is in the center of the line, and numbers to the left of the zero are negative, while the numbers to the right of zero are positive.

You can use a number line to add and subtract signed whole numbers. Here's how it works.

Example

8 + (–4) =

The number 8 is positive because there is no negative sign in front of it.

Start at zero. Then, move eight units in the positive direction (to the right), as shown here.

The sign in front of the 4 is – (negative). So you need to move four units in the negative direction (to the left) as shown here.

The answer is 4.

Here are some basic rules to help you add, subtract, multiply, and divide signed numbers.

Practice problems for these concepts can be found at:

Numbers and Operations Practice Problems: GED Math