Integers and Absolute Values
Here is a number line. +1 +2 +3 +4 +5 -5 -4 -3 -2 -1
An integer is a positive or negative number.
-5 -4 -3 -2 -1 +1 +2 +3 +4 +5 Positive integers are integers greater than 0. They can be written without + sign.
Negative integers are integers less than 0. They are written with a -5 -4 -3 -2 -1 +1 +2 +3 +4 +5 Negative integers are integers less than 0. They are written with a - sign.
Zero is neither negative nor positive. -5 -4 -3 -2 -1 +1 +2 +3 +4 +5 Zero is neither negative nor positive.
Here are some real-world examples…
Let’s write an integer for each situation. Weather: 5 degrees below Because this weather is below normal, the integer is written as -5.
Let’s write an integer for each situation. Rainfall: 5 inches above normal Because this rainfall is above normal, the integer is written as +5 or just 5.
Let’s write an integer for each situation. Banking: a deposit of $23 Because deposit is adding an amount to your bank account, it is +23 or just 23.
You can also graph integers on a number line.
. . . . (-4, -2, 0, 5) Graph this set on a number line. -5 -4 -3 -2 -1 +1 +2 +3 +4 +5 Just draw a point (or a dot) on the location of the integer. That’s all!
. . . (-5, -1, 3) You get the point, right? Pun totally intended. Graph this set on a number line. (-5, -1, 3) . . . -5 -4 -3 -2 -1 +1 +2 +3 +4 +5 You get the point, right? Pun totally intended.
Hey, have you noticed that -5 and 5 are each 5 units (spaces) from 0?
+1 +2 +3 +4 +5 -5 -4 -3 -2 -1 -5 and 5 are both 5 spaces away from 0. They have the same absolute value.
Absolute value of a number is the distance between the number and 0 on a number line.
And it’s written like this…
5 units 5 units +1 +2 +3 +4 +5 -5 -4 -3 -2 -1 5 = 5 -5 = 5
-5 = 5 5 = 5 This means that the absolute value of both -5 and 5 are 5 (distance from 0).
Let’s try this one… -4 = 4 4 units +1 +2 +3 +4 +5 -5 -4 -3 -2 -1
So…basically…
-560 560 = 2010 = -256,487 = 256,487 OK…I get it, I get it!
Now, you can even do this…
12 + 4 -12 + 4 = = 16 -5 - -1 5 - 1 = = 4 2 + -3 2 + 3 = = 5 -7 - 5 7 - 5 = 2 =
Good job!