Math CC7/8 – Sept. 28 Math Notebook Things Needed Today (TNT): Math Notebook/Pencil Math Notebook Topic: Mult/Dividing Positive/Negative Integers Homework: Multi/Dividing IntegersWS

Warm-Up WRITE down each problem & SOLVE Show ALL your work & THINKING

Multiplying and Dividing Integers

Rules for Multiplying & Dividing (+)/(-) Integers When multiplying and dividing integers there are two rules: When multiplying or dividing integers that have the SAME sign, the answer is POSITIVE. Positive ● positive = positive Negative ● negative = positive +7 ● +12 = +84 -6 ● –5 = +30

Rules continued… Rule 2: Positive ● negative = negative When multiplying or dividing integers whose signs are DIFFERENT, the answer will always be NEGATIVE. Positive ● negative = negative Negative ● positive = negative +8 ● –4 = -32 -5 ● +7 = -35

Rules for Multiplying Integers Make the vertical and horizontal lines of a tic-tac-toe game.

Rules for Multiplying Integers Place three positive signs going diagonal and negative signs in the rest of the remaining places. + - - - - + - - +

Rules for Multiplying Integers Now you can start from any side and go any straight direction and you will see the correct integer rule for multiplication. + -

Let’s Practice! What sign would the answer have in front of the integer??? -5 • -7 = ???

POSITIVE!!!

What sign will be in front of the answer?? How about… -6 • 9 = ??? What sign will be in front of the answer??

NEGATIVE!!!

Try this one! What sign will be in front of the answer??? -81 / +9 = ???

NEGATIVE!!!

Let’s solve some problems! -8 (–9) =

+72

+4 (+12) =

48

-45 / 5 =

-9

-63 / 7 =

-9

-8 (–11) =

88

Remember… When multiplying and dividing integers: Same signs = a positive Different signs = a negative

Practice….. 3 -1 -15 -28 24 -22 -4 -3 4 -11 – 4 15 – (-2) -1 – (-6) -5 + 8 -3 + 2 -11 + -4 3 -1 -15 -11 – 4 15 – (-2) -1 – (-6) -15 17 5 7 • -4 -8 • -3 -11 • 2 -28 24 -22 -36 ÷ 9 12 ÷ -4 -28 ÷ -7 -4 -3 4

Multiply the following fractions Try These: Multiply Multiply the following fractions

Solutions: Multiply

Divide the following fractions Try These: Divide Divide the following fractions

Solutions: Divide

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-65 / 5 -13 points -30 / 10 -3 miles per hour 48 / -6 -8 -35 / 7 -5 Or a decreased by 3 m/h -65 / 5 -13 points 48 / -6 -8 Average loss of 8 points per game. -35 / 7 -5 5degrees drop each day on average