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4). ? 28 Check: ( 7 )(4) = 28 = ? 4 Divide into 4 pieces. 28 7 7 7 7 7 7 7 7 7 = 28

5). ? 45 Check: ( 9 )(5) = 45 = ? 5 Divide into 5 pieces. 45 9 9 9 9 9 9 9 9 9 9 9 = 45

Division and Multiplication Have the Same Rules • If the 2nd number is negative, you Flip the sign of the answer.

-10 -2 -5 -5 -10 Flip to Pos. 6). = ? Yes. Divide into 2 pieces. 5 5 Will answer be Pos or Neg? Flip to Pos. 6). -10 = ? -2 Will the sign flip? Yes. Divide into 2 pieces. 5 5 -5 “F” stands for “Flip” -5 -10

5 Stay Neg. 7). - 45 = ? No. Divide into 5 pieces. -9 -9 -9 -9 -9 -9 Will answer be Pos or Neg? Stay Neg. 7). - 45 = ? 5 Will the sign flip? No. Divide into 5 pieces. -9 -9 -9 -9 -9 -9 -45

Flip to Neg. 8). 45 = ? -5 Yes. Divide into 5 pieces. 45 9 9 9 9 9 -9 Will answer be Pos or Neg? Flip to Neg. 8). 45 = ? -5 Will the sign flip? Yes. Divide into 5 pieces. 45 9 9 9 “F” stands for “Flip” 9 9 -9 -9

- 5 Flip to Pos. 9). - 40 = ? Yes. Divide into 5 pieces. 8 8 -8 -8 -8 Will answer be Pos or Neg? Flip to Pos. 9). - 40 = ? - 5 Will the sign flip? Yes. Divide into 5 pieces. 8 8 -8 -8 -8 -8 -8 -40

Let’s show the picture for both dividing and checking Checking our answers: Let’s show the picture for both dividing and checking

Flip Flip -3 -6 -6 -6 10). 18 Check: ( -6 )(-3) = 18 = ? Yes. Divide into 3 pieces. 18 6 Flip Flip 6 = 18 6 6 6 6 Flip -6 -6 -6

Flip Flip -3 -6 -6 -6 WHY flip when dividing by a negative? 18 = ? 18 So why should we flip it, here, too? 18 6 We flip it here (multiplying). Check: ( -6 )(-3) = 18 Flip 6 = 18 6 6 6 6 Flip -6 -6 -6

Flip? -20 Why NOT flip when dividing by a positive? -20 Check: ( ? )(4) = -20 = ? 4 Do we flip it here? So why can’t we flip it here? No. Flip? We need to end up with -20 -20

Try Without a Picture -100 Stay Neg. Flip to Pos. a). b). 2 No. Yes. 11). Will answer be Pos or Neg? Stay Neg. Flip to Pos. Will answer be Pos or Neg? a). b). -100 -40 = 50 + or -50 ? = 4 or ? -4 2 -10 Will sign flip? Will sign flip? No. Yes.

Independent Practice Try these at your own pace. Don’t worry about finishing them all—just be accurate.

Flip to Pos. 12). - 15 16). - 15 - 3 3 Flip - 15 Flip to Neg. 3 13). = 5 + 2(4 – 6 ) - 3 3 Flip - 15 + 2( ) 4 + - 6 Flip to Neg. 3 13). 15 + 2( ) = - 3 - 5 - 2 - 3 Flip - 5 + - 4 14). 15 – - 3 - 9 15 + + 3 = 18 17). - 8 + ( ) - 8 + - 2 - 2 15). - 15 + - 3 = - 18 4 + - 10 - 6