Lesson: Multiplying and dividing integers
3514
Views
88
Downloads
2
Favorites
Lesson Objective
We will be able to multiply and divide integers.
Lesson Plan
Do Now: (5 minutes)
1) 18   7
2) Identify the coefficient in the following equation: 3x + 2 = 9
3) 12 – 17
Direct Instruction:(15 minutes)
Students will write the following rule and examples in their notes:
Have students write the following rule and examples in their notes:
Direct Instruction:(15 minutes)
Yesterday we learned that when adding and subtracting integers, it’s important to remember “same signs add, different signs subtract”. Today we are going to take our knowledge of integer operations one step further and learn how to multiply and divide integers.
When we are multiplying integers, we are multiplying both the numbers and the signs. For example, x time – y gives us –xy. We remember from last week that same signs means add and different signs means subtract. So since we have two negatives, that really means that it is a positive.
If I multiply –x times y, I get – xy. Different signs, subtract, so I get –xy as my final answer.
We can also think about multiplication as repeated addition. If I have 4 x 2, it means I have 4 2 times, which is 4 + 4. If 4 + 4 = 8 then 4 x 2 =  8
We can also think about multiplication as repeated addition. If I have 4 x 2, it means I have 4 2 times, which is 4 + 4. If 4 + 4 = 8 then 4 x 2 =  8
Students will write the following rule and examples in their notes:
Rule: When multiplying integers, two negatives become a positive product. A negative and a positive make a negative product.
Ex. – 5 x 3 Ex. 4 x 5 Ex. – 8 x 3
We can use what we know about fact families to help us with integer division. Dividing a negative and a positive gives us a negative. Dividing two negatives gives us a positive.
Have students write the following rule and examples in their notes:
Rule: A negative divided by a negative is a positive. A positive divided by a negative is a negative.
Ex. 18 ÷ 3 = 6 Ex. 24 ÷ 3 = 8
Ex. 12 ÷ 3 = 4
Guided Practice: (5 minutes)
Complete the following problems as a class:
Assessment: (5 minutes)
Multiplying and dividing integers workout
Ex. 12 ÷ 3 = 4
Guided Practice: (5 minutes)
Complete the following problems as a class:
3 x 6
12 ÷ 2
12 x – 9
72 ÷ 6
Additional reinforcement of the skill can come from flashcards with multiplying and dividing integers.
Additional reinforcement of the skill can come from flashcards with multiplying and dividing integers.
Assessment: (5 minutes)
Multiplying and dividing integers workout
Lesson Resources
multiplying and dividing integers work out Assessment 
1,685

No comments at this time.
Add Comment
Comments