# Inverse

Inverse means the **opposite in effect**. The reverse of.

## The Inverse of Adding is Subtracting

Adding moves you one way, subtracting moves you the opposite way.

Example: **20 + 9 = 29** can be reversed by** 29 - 9 = 20** (back to where we started)

And the other way around:

Example: **15**** - 3 = 12** can be reversed by** 12 + 3 = 15** (back to where we started)

## The Inverse of Multiplying is Dividing

Multiplying can be "undone" by dividing.

Example: **5 × 9 = 45** can be reversed by **45/9 = 5**

It works the other way around too, dividing can be undone my multiplying.

Example: **10 / 2 = 5 ** can be reversed by **5 × 2 = 10**

### But Not With 0

You can't divide by 0, so don't try!

Example: **5 × 0 = 0** cannot be reversed by **0/0 = ???**