1. 4-2 Using Number Sense to Solve Equations and 4-3 Solving Equations by Adding and Subtracting

2. Equation- a math sentence with an equal sign.
Open Sentence- an equation with one or more variables.
Solution of an Equation- a value for a variable that makes an equation true.

3. Substitution
Find the solution of 12m = 108 by substituting 4, 7, and 9.
12(4) = (7) = (9) = 108
48 = = = 108
NO NO YES
The solution is 9.

5. Inverse Operations- operations that undo each other.
Addition and Subtraction
Multiplication and Division

6. When Solving Equations…
1.) Identify the variable.
2.) Isolate the variable.
3.) Get rid of whatever numbers are on the same side as the variable by using inverse operations.
4.) What you do to one side of the equal sign, you must do to the other.
5.) Do the math.

7. Solving Equations by Adding

9. Solving Equations by Subtracting

11. Practice Solve. 1.) x - 6 = -55 2. ) 34 = g + 25 3.) d + 261.9 = -48