The document discusses multiplication of integers. It explains that multiplying integers involves multiplying signed numbers, and that the product of the absolute values remains the same but the signs may differ. It provides two rules for the sign of the product: if two integers have the same sign, the product is positive, and if they have opposite signs, the product is negative. Examples are given to illustrate the rules.

1. Multiplication of Integers

2. Objective
At the end of the lesson, you will be able to
multiply integers.

3. Introduction
Before you proceed with this lesson, you
should have mastery in multiplication of
whole numbers.

4. Learn about It!
Multiplication of integers involves the
multiplication of signed numbers like -3 and
2, or -5 and -6. The product of the absolute
values remains the same but the signs may
be different.

5. Learn about It!
The sign rules for multiplication may be
summarized as follows:
•The product of two integers with the same
signs is a positive integer.
•The product of two integers with opposite
signs is a negative integer.

6. Examples
1. (-5) x (+6) = - 30
2. (-10) x (-5) = +50
3. (+7) x (-3) = -21
4. (+8) x (+2) = +16
5. (-4) x (-3) = +12

7. Try it!
1. (+10) x (-7)
2. (-3) x (+9)
3. (-7) x (-7)
4. (+5) x (-2)
5. (+4) x (+9)

8. Try it! Solution
1. (+10) x (-7) = -70
2. (-3) x (+9) = -27
3. (-7) x (-7) = +49
4. (+5) x (-2) = -10
5. (+4) x (+9) = +36

9. What Do You Think?
1. What is the product of (-2) x (-2) x (-2)?

10. Key Points
The product of two integers with the same signs
is a positive integer.
The product of two integers with opposite signs is
a negative integer.

11. Question 1
What is the sign of the product of a negative
integer and another negative integer?

12. Question 2
What is the sign of the product of a positive
integer and a negative integer?

13. Question 3
Find the product. (-5) x (-4)
a. -9
b. -20
c. 9
d. 20

14. Question 4
Find the product. (+11) x (-10)
a. -110
b. 1110
c. -1110
d. 110

15. Question 4
Find the product. (-12) x (+10)
a. -120
b. 22
c. -22
d. 120

16. Question 10
Six nonzero integers are multiplied to obtain a
negative product. Which of the following could be
the number of negative factors?
a. Four
b. Two
c. Six
d. three