Opposites

Opposite numbers are two different numbers that have the same absolute value.   For example, 4 and -4 are opposites because |4| = 4 and |-4| = 4.

More about opposite numbers:

  • When opposite numbers are added, the sum is zero.
  • To get the opposite of a number, change the sign.
  • The absolute values of opposite numbers are the same.
  • Opposite numbers are equidistant from 0 on a number line.

 

Examples of opposite numbers:

  • 10 and -10 are opposite numbers.
  • -4 is the opposite of 4
  • 0 is the opposite of 0
  • The opposite of the opposite of negative 3 is 3:   -(-3) = 3

Opposites come in handy because when added together we get 0. When you solve equations like x + 2 = 3, you are trying to get that extra number to disappear so that the variable is by itself. How do you do that? You add the opposite.

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