A slow way to calculate the distance between numbers on a number line is to count every number between them. A simpler, faster way is to find the distance through subtraction and absolute values. An absolute value is the positive representation for a number and is symbolized as |a|. For example, the absolute values of 3 and -3, or |3| and |-3|, are both 3. This method of number line distance works for numbers close together and far apart.
Select two numbers on the number line. For this example, the numbers are -9 and 5.
Subtract one number on the number line from the other number. For this example, -9 subtracted from 5 is 14. If subtracting 5 from -9, the answer would be -14.
Obtain the absolute value of the number line difference. For this example, the absolute value for either 14 or -14 -- that is, |14| or |-14| -- is 14. The distance between the two numbers is 14.
About the Author
Chance E. Gartneer began writing professionally in 2008 working in conjunction with FEMA. He has the unofficial record for the most undergraduate hours at the University of Texas at Austin. When not working on his children's book masterpiece, he writes educational pieces focusing on early mathematics and ESL topics.