Embed Size (px)
Citation preview
Positives and
Negatives
0 1 2 3 4 5-2 -1-4 -3
Meet Pete
The Positive Pirate
Together, they’re called the “Positives”
Now meet their arch enemies…
Ned
The Negative Ninja
Together, they’re called the “Negatives”
These two don’t like each other very much.
Every time they meet, they always fight
Yaaaar going down! Hiiii-Yah!
And they ALWAYS destroy each other in the process
So what happens when a lot of positives…
…are confronted by a bunch of negatives
+11 Positive is left after the battle -3
3 negatives
+44 positives
-33 negatives are
left
+5-8
+15-7
+88 Positives are
left
When you’ve got 2 positives…
+4 +5
Hi! Hello!
They combine to make a bigger positive!
+99 Positives
-8-4
-1212 Negatives
-4 and -8 combined equals…
Hello!
Hi!
So lets review what we learned…
+1 -1 = 0-3 +4 = +1-8 +5 = -3
-7 +15 = +8+4 +5 = +9-4 -8 = -12
Take Note:
+1 -1 = 0-3 +4 = +1-8 +5 = -3
-7 +15 = +8+4 +5 = +9-4 -8 = -12
Take Note:
+1 -1 = 0-3 +4 = +1-8 +5 = -3
-7 +15 = +8+4 +5 = +9-4 -8 = -12
When you have a positive and a
negative number, you
subtract
Take Note:
+1 -1 = 0-3 +4 = +1-8 +5 = -3
-7 +15 = +8+4 +5 = +9-4 -8 = -12
When you have a positive and a
negative number, you
subtract When you have 2 positives or 2 negatives, you add them up
+1 -1 = 0-3 +4 = +1-8 +5 = -3
-7 +15 = +8+4 +5 = +9-4 -8 = -12
But after we subtract, how do we know whether the
answer will be positive or negative?
For Example…
-12 +9 = -3The larger number always wins!
Since there are more negatives than positives, the answer is negative
For Example…
-3 +7 = +4The larger number always wins!
Since there are more positives than negatives, the answer is positive
Sample Problems
Who Will Win The Battle?Will the answer be positive or negative?
+8 -14 = +2 -4 =-13 +15 =-9 -4 =-28 +31 =+2 +16 =
+
- -
+ -
+
Who Will Win The Battle?Should you add or subtract?
+8 -14 = +2 -4 =-13 +15 =-9 -4 =-28 +31 =+2 +16 =
+
- -
+ -
+
Subtract
Subtract
Subtract
SubtractAdd
Add
Who Will Win The Battle?Solve the problem
+8 -14 = +2 -4 =-13 +15 =-9 -4 =-28 +31 =+2 +16 =
+
- -
+ -
+
6
2 13
3
18
2
Subtract
Subtract
Subtract
SubtractAdd
Add
