Integers Blast Off 3 4 5 6 7 8 10 9 2 1

Integers The integers are the set of numbers that include the positive whole numbers, zero and the negative whole numbers

Number Line bigger numbers smaller numbers -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 smaller numbers

Comparing integers Remember: > stands for ‘is greater than’ and the symbol < stands for ‘is less than’ So -4 is < 2, because it is to the left of 2 on the number line, and -2 > -5, because it is to the right of -5 in the number line. -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7

Adding Integers     move to the right on the number line -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7     eg 1: -1 + 5 = 4 eg 2: -7 + 2 = -5

Subtracting Integers     move to the left on the number line -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7     eg 1: 2 - 3 = -1 eg 2: -3 - 4 = -7

Rules for Adding and Subtracting It helps to use a number line when adding and subtracting When there are two signs between a pair of numbers. + + replace with + - - replace with + - + replace with - + - replace with - signs the same, replace with + signs different, replace with -  - 2 - + 3 = 2 3 = -1 + -4 - - 5 = -4 5 = + 1  4 + - 6 = 4 6 = - -2 + - 7 ++4 = -7 4 = + -3   -4 + 5 - -2 + -1 = -4 + 5 + 2 - 1 = 2

Multiplying & Dividing Integers + x + = +  x  = + + x  =   x + =  + ÷ + = +  ÷  = + + ÷  =   ÷ + =  If there are an odd number of negative signs, the answer is negative. e.g. -4 x 2 = 5 x - 6 = -4 x - 3= 3 x 5 = -2 x - 4 x -5 = - 8 e.g. 12 ÷ -6 = -14 ÷ -2 = -12 ÷ 4 = 24 ÷ 6 = - 2 - 30 7 12 - 3 15 4 - 40