Inverse Operations undo each other
Addition & subtraction are inverse operations
Multiplication &division are inverse operations
We can use these relationships between inverse operations to simplify some numerical and variable expressions
17- 8 + 8 instead of doing 17 - 8 and then adding 8 again simply cancel the + and the -
That is, 17 - 8 + 8 = 17
9 - x + x = 9 because adding x and subtracting x are inverse operations and they undo each other...
108 ÷ 6 × 6 ... the long way would be to divide 108 by 6 first. That's 18 and then multiply 18 by 6 and get 108.. but why do that? Using the inverse operations you realize that multiplication and division undo each other so 108 ÷ 6 × 6 is simply 108
3n ÷ 3 = 3
Subtraction Property of Zero
For any whole number a
a-0 = a and a-a = 0
In Algebra
a- a = 0 is called the Property of Opposites ( The Prop of Opp's)
Division Property of One
For any whole number a, except 0
a ÷ 1 = a and a ÷ a = 1
Division Property of Zero
For any whole number a, except 0
0 ÷ a = 0
Remember we discussed that we can never divide any number by 0
We said that any number
a ÷ 0 was said to be 'undefined.'
