|
|
Chapter 2 Integers 2-7 Multiplying Signed Integers Preview
Multiplying Signed Integers The procedure for multiplying signed integers is: - Step 1: Multiply the absolute value of the factors.
- Step 2: Give the appropriate sign to the product:
- Positive if the both factors have the same sign.
- Negative if the factors have opposite signs.
| |
Figure 2-x. Terminology for the multiplication of signed integers.
| Multiplying Integers Having the Same Sign Procedure When the factors have the same sign—both positive or both negative—the product is always positive. So you simply multiply the two factors, ignoring their signs, and make the product positive. It's that simple. | |
Multiplying integers having the same sign.
| Example (+ 5) x (+ 2) = ? | The Problem | x | ( + 5) x (+ 2) = ? | Step 1:Multiply the absolute value of the terms. | | + 5 | x | +2 | = 10 | x | Step 2: Assign the appropriate sign to the product. | Signs are identical, so the sign is +: +10 | x | | The Solution | x | (+ 5) x (+ 2) = ( +10) Or you might see it expressed more simply as: 5 x 2 = 10 | Example ( – 8) x ( – 3) = ? | The Problem | x | ( – 8) x ( – 3) = ? | Step 1: Multiply the absolute value of the terms. | | –8 | x | –3 | = 24 | x | Step 2: Assign the appropriate sign to the product. | Signs are identical, so the sign is +: +24 | x | | The Solution | x | ( – 8) x ( – 3) = ( +24) Or you might see it expressed more simply as: – 8 x – 3 = 24 | Examples and Exercises Multiplying Integers Having the Same Sign Use these interactive examples and exercises to strengthen your understanding and build your skills: | | Multiplying Integers Having Opposite Signs Procedure When the factors have opposite signs — one is positive and the other is negative (it makes no difference which is which) — the product is always negative. So you simply multiply the two factors, ignoring their signs, and make the product negative. | |
Multiplying integers having opposite signs.
| Example (– 7) x (+ 2) = ? | The Problem | x | (– 7) x (+ 2) = ? | Step 1: Multiply the absolute values of the factors. | 7 x 2 = 14 | x | Step 2: Assign a negative sign to the product. | – 14 | x | | The Solution | x | (– 7) x (+ 2) = (– 14) Or you might express this answer more simply as: – 7 x 2 = -14 | Exercises Complete the multiplication operations.
Click the ? symbol to see the correct answers. | 1. (+ 6) x (+ 2) = ? | 2. (– 9) x (– 3) = ? | | 3. (+ 8) x (– 9) = ? | 4. (– 6)(+ 2) = ? | | 5. (– 30)(+ 5)= ? | 6. (+ 10) � (– 4) = ? | | 7. (– 4)(– 7) = ? | 8. (+ 24) � (+ 1) = ? |
|
