1. EQ: How do I solve an equation in one variable?
1.1 Solving Equations
Properties of E quality

2. Properties of Equality
An equation is a mathematical sentence that uses the equal sign = to show two expressions are equivalent. A solution of an equation is a value for the variable that makes the equation true. To determine the solution of an equation, you will use the Properties of Equality.

3. Addition Property of Equality
Whatever is added to one side of the equal sign must be added to the other side.

4. Addition Property of Equality, Continued….
For Example:
𝑥−5=7
+5 +5
𝑥=12

5. Subtraction Property of Equality
Whatever is subtracted from one side of the equal sign must be subtracted from the other side.

6. Subtraction Property of Equality, Continued…
For Example:
𝑥+5=7
−5 −5
𝑥=2

7. Multiplication Property of Equality
Whatever is multiplied on one side of the equal sign must be multiplied on the other side.

8. Multiplication Property of Equality, Continued…
For Example:
𝑥 3 =9
(3) 𝑥 3 =9 3
𝑥=27

9. Division Property of Equality
Whatever is divided on one side of the equal sign must be divided on the other side.

10. Division Property of Equality, Continued…
For Example:
3𝑥=27
3 3
𝑥=9

11. Associative Property of Equality
The associative property states that you can add or multiply regardless of how the numbers are grouped.
For Example:
Associative Property for Addition:
2+7+5=2+7+5
2+7 +5=2+ 7+5
9+5=2+12
14=14

12. Associative Property of Equality, Continued…
Another Example:
Associative Property for Multiplication:
3∗4∗2=3∗4∗2
3∗4 ∗2=3∗ 4∗2
12 ∗2=3∗ 8
24=24