Multiplication of Integers Lesson Plan

MULTIPLICATION OF INTEGERS

Time Frame: 60 minutes Objectives: In this lesson students are expected to: 1. multiply integers and; 2. apply multiplication of integers in solving problems. Prerequisites: Addition and Subtraction of Integers Lesson Proper: I. Review/Drills Review on how to add or subtract integers. 1. 5 + -2 2. 2 + 9 3. -5 + -6 4. 4 – (-3)  – (-3) 5. 7 – 9  – 9 II.

Activity 1 Each group of students will be given a copy of this multiplication table and will fill in the blank boxes with products of numbers aligned to the box’s box’s row and column. Hint; try to look for patterns to complete the puzzle. (Give an example based o n the products already given below.) -3

-2

-1

0 0

1 3

2

3 9

2 0

multiply 3 2 1 0 -1 -2 -3

After completion of the table, answer the following: 1. What is your answer if we multiply 2 by 3? How did you come up with your answer? 2. How did you find the product of -1 and 3? 3. -2 x -2 = _______. 4. What is your answer if we multiply 0 by 1? Or 0 by – by – 2  2 or 3? 5. Can you see some patterns in the t he table? Can you explain how the patter n works?

III.

Analysis Activity 2 A. Answer the following: 1. a. Fill in the blanks 4 x 3 = ___________ 3 + 3 + 3 + 3 = ____________ 4 + 4 + 4 = _________ b. Compare the examples above. What do they have in common? c. Is 4 x 3 equal to 3 + 3 + 3 + 3 and 4 + 4 + 4? Explain. d. How are multiplication and addition related? e. Complete the sentence, “Multiplication is __________ addition.” 2. (- 6) x 3. Let‘s extend Let‘s  extend this using repeated addition. What should we be adding? What is the result?

3. 5 x (-2). Rewrite this expression as a repeated addition? What is the result?

B. we can also use REPEATED SUBTRACTION in this examples 2 and 3 -3 – 3 – 3 – 3 – 3 – 3 = -3 + -3 + -3 + -3 + -3 + -3 = - 18 - 5 – 5 = -5 + (-5) = -10 4. ( – 6) x (- 2). Express this using repeated subtraction. What is the result?

5. What happens if we multiply two negative integers?

6. Express 5 x 0 as repeated addition or subtraction. Is it even possible?

IV.

Abstraction Explain on how to multiply integers.

V. Application Find the product of the following 1. 5(12) = 2. (-8)(4) = 3. -5(3)(2) = 4. -7(4)(-2) = Give an arithmetic equation which will solve the following. 1. The messenger came and delivered 6 checks worth P50 each. Are you richer or poorer? By how much? 2. The messenger came and took 3 checks worth P120 each. Are you richer or poorer? By how much? 3. The messenger came and delivered 12 bills for P86 each. Are you richer o r poorer? By how much? 4. The messenger came and took away 15 bills worth P72 each. Are you richer or poorer? By how much?

ASSIGNMENT/EXTENSION: The truth about LOVE and HATE is if you: LOVE to LOVE = LOVE HATE to HATE =LOVE

HATE to LOVE = HATE LOVE to HATE = HATE

1. Are these statements true? Prove your answer. 2. How are these related to multiplication of integers? 3. Construct positive and negative traits that can create similar to the example above that illustrates the rules in multiplication of integers.

Prepared by:

LARK LEMUEL O. ISLES Division of Laguna Plaridel National High School