Absolute Values

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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!

number line

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