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1. Adding Integers Cornell Notes for September 2- September 3

2. Do you remember what an Integer is ? • Integers are the set of whole numbers and their opposite: • -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5 …..

3. So now that you remember….. • We are going to do some magic and add and subtract them today. • I know you are so excited!!!!....me too!!!

4. Where do we actual see/use adding and subtracting integers in the real world? • Have you ever played football or watched football? • On a football field forwards progress is represented by a positive integer and being pushed back is represented by a negative integer (in yards).

5. Lets take a look at the concept: • http://www.brainpop.com/math/numbersandoperations/addingandsubtractingintegers/

6. Adding Integers on a Number Line • -2 + (-3) • Always just think money!!! • +(-3) • * ^ ^ * • -7-6-5-4-3-2-1 0 1 2 • -2 + (-3) • You owe \$2 (-2) and you borrow(+) \$3 more (-3). Now how much do you owe? \$5 . You are -\$5

7. Add integers with the Same Sign • Find -4 + (-5) Both numbers are negative, so the sum is negative. [-4] + [-5] = -9 You owe \$4 (-4), and you borrow (+) another \$5 (-5). Now you are negative \$9. (-9)

8. Try the counter method …. 5 + (-3) +++++ _ _ _ Cancel the + and – with each other. The remaining sign is the sign you use and the number of signs is you number…… +2

9. Adding with different signs • 7 + (-4) • Take the sign of the larger number. • 7 is the larger # and its positive the answer will be positive. Really is like 7-4 =3 When you add a negative its just like subtracting.

10. Adding more than two integers. • 9+(-3) +(-9) • -4+6+(-3)+9 • Look at areas you can cancel……9+(-9)= 0 • So… (-3) remains. • Answer= -3 • Order does not matter so add positives first. • 6+9=15 • 15-4+(-3) • 15-4=11 • 11+(-3) Same as subtracting • 11-3= 8 Wahoo!!

11. Last Slide of Notes…Promise!!! • Vocab. • Additive Inverse (aka Opposite) • Same absolute value, different sign • |8| and |-8|

12. Practice Page 67 in your textbook • Do #1- 15, and 30-41 • This is independent work ….no discussion off topic of simply asking your immediate( right next to you neighbor) or myself for assistance. This is a concept that truly takes practice and application. You need to make good use of this time to be successful. Creating a number line is recommended. Use your handout. DO WORK!!

13. Need more help with this ? Check out this site for more useful examples: http://www.mathleague.com/help/integers/integers.htm