Embed Size (px)
Citation preview
Integers
What????
Integers+
+
-
-
An integer is a whole number (not a fraction) that can be positive, negative, or zero. Therefore, the numbers 10, 0,
-25, and 5,148 are all integers.
IntegersKnow the signs
+ Positive (If it has NO sign, it is
POSITIVE.)
- Negative (AKA: opposite of)
Integers-
+
+
-
In order from least to greatest
-25, -5, -2, 0, 10, 51, 78
Integers+
+
-
-
Correct order from least to greatest?
5, -1, -5, 1, 11, -11, 0
-11, -5, -1, 0, 1, 5, 11
The correct order is…
Adding
Think MONEY!!
$$$$ $$$$
AddingSigns the same??Add and keep the
signs+2 + +3 = -2 + -3 =
+5-5
Think MONEY!!
Sue has $2. Nancy gives her $3. Has much does Sue have now?
+2 + +3 = +5
Think MONEY!!
Sue owes $2. She needs to pay Miss Dixson $3. How much does Sue owe now?
-2 + -3 = -5
AddingSigns different??Actually subtract
Keep the sign of the “larger” number
AddingSigns different??
+2 + -3 = -1(3 - 2 =1 Use the
sign of the 3 because 3 is larger than 2)
AddingSigns different??
Sue wrote a check for $2. Billy gave Sue $3. How
much does Sue have now? -2 + +3 = +1
Adding
Think MONEY!!$$$$ $$$$
Remember When
SubtractingDo you already know how
add integers?
YES!
Cool!
If you know how to add, you can also subtract.
Subtracting
SubtractingChange the sign of the
2nd integer and add
That’s it! Easy, huh?
+2 - -3 = +5
Subtracting
Change the sign of the 2nd integer and add
ALWAYS the 2nd integer
SubtractingChange the sign of the 2nd
integer and add (Now it is just like what we’ve done in the past.)
+2 - -3 =+5
MultiplyingIf the signs are the same, the
product will be positive.
+ x + = + - x - = ++2 x +3 = +6-2 x -3 = +6
MultiplyingIf the signs are different, the
product will be negative.
+ x - = - - x + = -
+2 x -3 = -6-2 x +3 = -6
DividingIf the signs are the same, the result will be positive.
+ ÷ + = + - ÷ - = ++6 ÷ +3 = +2-6 ÷ -2 = +3
DividingIf the signs are different, the result will be negative.
+ ÷ - = - - ÷ + = -
+6 ÷ -3 = -2-6 ÷ +3 = -2
IntegersAren’t they
fun????
