Integer Rules

Positive and negative whole numbers (no fractions)

Same signs, add and keep the sign

Positive + Positive = Positive

4 + 5 = 9

Negative + Negative = Negative

(-4) + (-5) = -9

Opposite signs - Subtract the numbers and keep the sign of the bigger number

(-4) + 5 = 1

4 + (-5) = -1

Change the signs ("add the opposite")

Keep the sign of the first number

Change the subtraction to addition

Change the sign of the second number to the opposite sign.

If it is positive- change to negative.

If it is negative- change to positive. 

(4) - (-4) = 4 + 4 = 8

(-5) - (-5) = -5 + 5 = 0

4 - (-5) = 4 + 5 = 9

SAME SIGNS- POSITIVE. Multiply the numbers. Answer will be positive. 

(-5) × (-5) = +25

DIFFERENT SIGNS- NEGATIVE. Multiply the numbers. Answer will be negative

(+5) × (-5) = -25

SAME SIGNS- POSITIVE. Divide the numbers. Answer will be positive. 

(-5) ÷ (-5) = +1 

DIFFERENT SIGNS- NEGATIVE. Divide the numbers. Answer will be negative 

(+5) ÷ (-5) = -1