What am I Learning Today?

1
What am I Learning Today?

• Integers

How will I show that I learned it?
Subtract positive and negative integers
accurately
2
Hands On Investigation

• 1
• -1
• 0 (ZERO PAIR)
• When you model subtracting numbers with the same
  sign, you simply take away chips to find the
  difference.
• When you model subtracting numbers with different
  signs, you need to add zero pairs before you can
  take away chips.

3
QUESTION

• How do I subtract integers?

4

• Use the additive inverse
• Change the subtraction sign to addition
• Change the second number to its opposite
• Follow the addition rules

9 (- 5)
9 5 14
5
Solve These Problems

• 3 (-5)
• -4 (-7)
• 3 - 4
• -6 - 7
• 5 (-9)
• -9 (-9)

8
3 5
3
-4 7
-1
3 (-4)
-13
-6 (-7)
14
5 9
0
-9 9
6
Lets Try a Word Problem
On January 1, 2002, the high temperature was
81F in Kona, Hawaii. The low temperature was
-29F in Barrow, Alaska. What was the difference
between the two temperatures?
110F
http//my.hrw.com/math06_07/teacher/osp/msm2_ga/da
ta/chap02/section03/practice_b.pdf
7
Lets Try a Few More 1. 2 6 2. 3 -
(4) 3. 7 - (5) 4. 3 - (4) 5. 6 -
(1) 6. 6 - 1
-8
1
12
7
-5
-7
8
Lets SUM it up

• Keep it, change it, flip it??
• Keep the first number the same
• Change the operation to addition
• Flip the number to the other side of the number
  line (use its opposite)
• SUBTRACTION means add the opposite