Multiplying and Dividing Integers TeacherTwins©2014

Warm Up 6 11 -6 -11 Leave, change , opposite 9+ 9 = 18 Add or subtract. 1). −𝟑+𝟗 2). 𝟗− −𝟐 3). 𝟗+−𝟏𝟓 4). −𝟓+−𝟔 5). Explain how to change the following problem to an addition problem and solve. 𝟗−(−𝟗) 6 11 -6 -11 Leave, change , opposite 9+ 9 = 18

Look at the patterns below. Start at zero and add -4 two times. Multiplication is repeated addition. 2(-4) = -8 2(4) = 4 + 4 = 8 2(-4) = -4 + -4 = -8 -4 -4 Look at the patterns below. -2 ∙ 2 = -4 -2 ∙ 1 = -2 -2 ∙ 0 = 0 -2 ∙ (-1)= 2 -2 ∙ (-2) = 4 -4 ÷ −𝟐 = 2 -2 ÷ −𝟐 = 𝟏 0 ÷ −𝟐 = 𝟎 2 ÷ −𝟐 = −𝟏 4 ÷ −𝟐 = −𝟐 The problems above show that when you have signs that are different the product or quotient is negative. The problems also show that when you have the same signs the product or quotient is positive.

Multiplying Integers Dividing Integers Multiplying and Dividing Integers Flippable Multiplying Integers Dividing Integers

If the signs are different the product will be negative. Multiplying Integers To multiply integers you multiply like normal and follow the following rule to figure out the sign of the product. If the signs are different the product will be negative. If the signs are the same the product will be positive. Examples: a). -4(-8) b). 7(-3) c). -5(2) d). 3(10) 32 -21 -10 30

Dividing Integers To divide integers you divide like normal and follow the following rule to figure out the sign of the quotient. If the signs are different the quotient will be negative. If the signs are the same the quotient will be positive. Examples: a). 𝟑𝟔÷−𝟑 b). −𝟏𝟓÷−𝟏𝟓 c). −𝟐𝟓𝟎÷𝟏𝟎 d). 𝟕𝟎÷𝟓 -12 1 -25 14

Closure List 3 multiplication problems that have a product of -12. Use both positive and negative factors.