Integers

Positive and Negative Numbers on the Number Line

Adding and Subtracting Integers

Background Knowledge

Integers

  1. Whole numbers (0,1,2,3,...) and their opposites (-1, -2, -3,...)

  2. Parts of whole numbers (fractions and decimals) are NOT integers.

Rules for Adding Integers

  1. If the signs are the same, add and keep the sign. (-2 + -3 = -5)

  2. If the signs are different, subtract and keep the sign with the largest absolute value. (-9 + 17 = 8 OR 13 + -18 = -5)

Rules for Subtracting Integers

  1. Turn Subtraction into Adding the Opposite. (10 - 16 = 10 + -16)

  2. Follow the Rules for Addition

Multiplying and Dividing Integers

Background Knowledge

Integers

  1. Whole numbers (0,1,2,3,...) and their opposites (-1, -2, -3,...)

  2. Parts of whole numbers (fractions and decimals) are NOT integers.

Rules for Multiplying and Dividing Integers

  1. If the signs are the same, the answer is positive.

  2. If the signs are different, the answer is negative.