The absolute value of a number is its distance from zero.
Yes, the ACT and the SAT check to see whether you know this. Sorry!
Since the number -3 is three (3) spaces from zero, its absolute value is 3.
Absolute value is notated by those vertical line thingies: |
|. This notation was introduced by some Prussian mathematician in 1841, . . . but, who cares?
- | 1 | =1
- | -1 |=1
- | -2 | =2
- | -3 |=3
- | 1-4 |=3
- | 2-6 |=4
- | 12-13 |=1
- | 25-20 |=5
- | 995-1000 |=5
- | 500-600 |=100
- | x | =x
- | -x |=x