2.5+Multiplying+Integers

Section 2.5 - Multiplying Integers
We already learned that multiplication was repeated addition. So 3 x 4 means 4 + 4 + 4 = 12. It works the same way when multiplying negative numbers. 3 x ( - 4) means ( - 4 ) + ( - 4 ) + ( - 4 ) = ( - 12) if you count down on the numberline. Basically, you are just multiplying the numbers (absolute values) and then worrying about whether the answer is positive or negative.


 * If the signs are different, the answer is always negative. **
 * If the signs are the same, the answer is always positive. **

3 x 4 = 12 -3 x 4 = -12 3 x -4 = -12 -3 x -4 = 12

This triangle often helps when multiplying (or dividing) integers:



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 * Practice Problems for this Section**

**Where to from here?**
2.1 Integers 2.2 Absolute Value 2.3 Adding Integers 2.4 Subtracting Integers 2.5 Multiplying Integers 2.6 Dividing Integers 2.7 Exponents and Roots Chapter Two Summary Chapter Two Homework