Inverse Properties

Additive Inverse:

a + (-a) = 0 or (-a) + a = 0

The sum of a number and its additive inverse is zero.

Any number plus its opposite is zero.

Example:

9 + (-9) = 0

4x + (-4x) =0

Your mother gave you $10 to buy lunch on the field trip and you spent $10.  Now you have no money.

10 + (-10) = 0

Multiplicative Inverse:

a * (1/a) = 1  for all real numbers, except a=0

The multiplicative inverse of a number a (written as 1/a or a^-1) is the number that, when multiplied by a, gives the result of 1.

Any number times its reciprocal is 1.

Example:

2 * ½ = 1

You bought 4 hotdogs at the baseball game and you split them between you and three friends.  You only get ¼ of the order, so you get one hotdog.

4*(1/4) = 1

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