Absolute value is the distance from zero on a number line. Because it refers to a distance, absolute value is always positive. We use two vertical bars to represent absolute value. If we wanted to take the absolute value of -3, it would look like this: |-3|. This means “find the absolute value of -3” (or the distance that -3 is from zero).
You can find this using one of two ways:
- What is the positive value for this number?
- How far from 0 is the number on a number line?
Here is another example. The symbol for absolute value is shown in this equation: |8| = 8 and |-8| = 8. These are read as “The absolute value of 8 equals 8” and “the absolute value of negative 8 equals 8.” These are true because the distance between 0 and 8 on the number line is 8 spaces and the distance between 0 and -8 on the number line is 8 spaces. Distance is always positive. One can never travel a negative distance.
Let’s look at the number line first.
Since -3 is 3 units away from 0 on a number line, then the absolute value of -3 is 3. Without a number line, then you take the positive value for -3. So, |-3| = 3
Here are some basic examples:
| 5 | = 5
| -2 | = 2
| 0 | = 0
The distance between a number and zero on the number line is called absolute value.
To solve |-5 + 4|= ? You first solve what’s inside and get -1 and then find the absolute value, which is 1. To solve |10| + |-6|= ? You first find the absolute value of each and then add them 10 + 6 = 16.
Practice
1) What is the absolute value of 21?
2) What is the absolute value of -4?
3) |-10| = ?
4) |-3 + 1|= ?
5) |2 + 3|= ?
6) |0| = ?
7) |14 – 20|= ?
8) |-9 – 2|= ?
9) |2| + |-18|= ?
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