An operator is a symbol such as the following: x , + , - , /
Depending on increase or decrease your operator will change.
An equation which decreases will use the symbols: / , -
e.g 4 / 2 = 2
e.g 3 - 1 = 2
An equation which increases will use the symbols: + , x
e.g 2 x 3 = 6
e.g 2 + 3 = 5