Here’s -3 minus a -2
-3 - (-2) = -1
Here’s -2 minus a -3
-2 - (-3) = 1
• Rules: • 1.) ALWAYS MAKE 2 MARKS • 2.) The marks are made between the two numbers.
Changing Subtraction to Addition
•
•
•1.) -3 - 7 • -3 - 7
Examples (Simplify)
-3 + (-7) -10
Remember if the signs are the same you add
•2.) -2 - (-5) • -2 - (-5)
Examples (Simplify)
•
•
-2 + 5 3
Remember if the signs are different you subtract
Examples (Simplify) Remember if the signs •3.) 3 - 7 are different • 3-7 you
• • 3 + (-7) -4
subtract
•4.) 2 - (-5) • 2 - (-5)
Examples (Simplify)
Remember if the signs are the same you add
• •
2+5 7
•5.) (-6 - 7) - (-8) • (-6 - 7) - (-8)
Examples (Simplify)
• •
-13 - (-8)= -13+8
-5
1.) 11 -3 2.) 7 - (-2) 3.) -6 -9 4.) -3 - (-5)
Change to Addition
5.) 7 -(-3) 6.) 5 - 2 7.) -6 -(-9) 8.) -3 - 5
1.) 11 - 3 2.) 7 - (-2) 3.) -6 - 9 4.) -3 - (-5)
Change to Addition
5.) 7 -(-3) 6.) 5 - 2 7.) -6 -(-9) 8.) -3 - 5
Closure #1
• To change subtraction to addition, How many marks do you always make?
Closure #2
• To change subtraction to addition, where do you make the marks?