OPERATIONS ON INTEGERS

Positive and Negative Integers with Operations

Adding Rules:

·        Positive + Positive = Positive       e.g  5 + 4 = 9 

·        Negative + Negative = Negative  e.g (- 7) + (- 2) = - 9 

·        Sum of a negative and a positive number :-Use the sign of the larger number and subtract e.g

            (- 7) + 4 = -3

                  6 + (-9) = - 3 

                 (- 3) + 7 = 4

                 5 + ( -3) = 2.

Subtracting Rules:

·        Negative - Positive = Negative  e.g(- 5) - 3 = -5 + (-3) = -8

·        Positive - Negative = Positive + Positive = Positive   e.g 5 - (-3) = 5 + 3 = 8 

·        Negative - Negative = Negative + Positive = Use the sign of the larger number and subtract

          (Change double negatives to a positive.)

          (-5) - (-3) = ( -5) + 3 = -2

          (-3) - ( -5) = (-3) + 5 = 2

Multiplying Rules

·        Positive x Positive = Positive           e.g 3 x 2 = 6

·        Negative x Negative = Positive        e.g (-2) x (-8) = 16 

·        Negative x Positive = Negative       e.g(-3) x 4 = -12

·        Positive x Negative = Negative       e.g 3 x (-4) = -12

Dividing Rules

·        Positive ÷ Positive = Positive          e.g 12 ÷ 3 = 4 

·        Negative ÷ Negative = Positive   e.g(-12) ÷ (-3) = 4 

·        Negative ÷ Positive = Negative   e.g (-12) ÷ 3 = -4

·        Positive ÷ Negative = Negative   e.g 12 ÷ (-3) = -4