The document defines positive and negative numbers, with positive numbers being greater than zero and negative numbers being less than zero. It provides examples of how negative numbers are used to measure temperatures below zero, depths under sea level, and debt. It then explains how to add and subtract integers using a number line, with direction determined by the sign of the number. Finally, it briefly discusses multiplying integers and taking the square root of positive and negative numbers.
8. Negative Numbers Are Used to
Show Debt
Let’s say your parents bought a car but
had to get a loan from the bank for $5,000.
When counting all their money they add
in -$5.000 to show they still owe the bank.
9. Positive & Negative Numbers
Working with positive and negative
numbers is like driving in traffic.
You have to watch the traffic signs
and follow the driving rules.
10. Hint
• If you don’t see a negative or
positive sign in front of a
number it is positive.
+9
11. One Way to Add Integers Is With
a Number Line
When the number is positive count
to the right.
When the number is negative count
to the left.
- +
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
12. One Way to Add Integers Is With
a Number Line
+3 + -5 = -2
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
13. One Way to Add Integers Is With
a Number Line
+6 + -4 = +2
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
14. One Way to Add Integers Is With
a Number Line
+3 + -7 = -4
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
15. One Way to Add Integers Is With
a Number Line
-3 + +7 = +4
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
16. One Way to Add Integers Is With
a Number Line
-5 + +3 = +4
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
17. One Way to Add Integers Is With
a Number Line
-2 + +8 = +6
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
18. One Way to Add Integers Is With
a Number Line
-5 + +2 = -3
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
19. One Way to Add Integers Is With
a Number Line
-4 + -2 = -6
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
20. One Way to Add Integers Is With
a Number Line
-2 + -3 = -5
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
21. One Way to Add Integers Is With
a Number Line
-1 + -4 = -5
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
22. One Way to Add Integers Is With
a Number Line
-4 + -1 = -5
-
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-
23. One Way to Add Integers Is With
a Number Line
4+1= 5
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
24. One Way to Add Integers Is With
a Number Line
3+2=5
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
25. One Way to Add Integers Is With
a Number Line
1+5= 6
+
-6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
+
28. Subtracting Integers
• Adding a negative number is the same as
subtracting a positive number.
1 + -5 = 1 - 5
• Subtracting a negative number is the same
as adding a positive number.
1 - -5 = 1 + 5