Notes from Class! Find pictures of our notes HERE online! :) Expressions and Equations

If you struggle with any of these items at home, please come in for tutoring after school! :)
Solving Expressions-
Use PEMDAS!

                          

Solving One Step Equations-
1. Isolate the variable by using the inverse operation! (do the opposite of what is being done to the variable!)
2. What you do on one side you must do to the other (properties of equality)

Inverse operation of subtracting is adding

Inverse operation of adding is subtracting

Inverse operation of dividing is multiplying

Inverse operation of multiplying is dividing

Properties of Numbers

Associative Property-
Grouping changes
(4 + 1) + 2 = 4 + (1 + 2)
Works for multiplication and addition ONLY

Commutative Property-
Position changes
7 + 3 = 3 + 7
Works for multiplication and addition ONLY

Identity Property-
Number keeps it's own identitiy
7 x1 = 7 multiplicative identity
7 + 0 = 7  additive identity

Distributive Property-
Distribute the number outside of the ( )'s to the numbers inside ( )'s using multiplication
3(x + 5) = 3x +15
Solving TWO STEP EQUATIONS
*Work towards the variable (undo what's hanging off the side by the variable first, then undo what is right next to the variable)
*Use the inverse operation to get the variable by itself (opposite operations)
*What you do on one side you must do to the other