1. Solving One-Step Equations

2. Created by S. Koch - 2003 3x – 6y + 18 = 0 What are your coefficients? What is your constant? 3, -6 18

3. What you do to one side of the equation must also be done to the other side to keep it balanced. An equation is like a balance scale because it shows that two quantities are equal.

4. Created by S. Koch - 2003 Solving one-step equations: A one-step equation means you only have to perform 1 mathematical operation to solve it. You can add, subtract, multiply or divide to solve a one-step equation.

5. What is the variable? To solve one step equations, you need to ask three questions about the equation: What operation is performed on the variable? What is the inverse operation? (The one that will undo what is being done to the variable)

6. Created by S. Koch - 2003 Solving an addition equation : t + 7 = 21 Get rid of the 7 by adding its opposite to both sides of the equation. t + 7 = 21 -7 t = 14 Example 1

7. Created by S. Koch - 2003 Solving a subtraction equation : g – 6 = 40 Get rid of the 6 by adding its opposite to both sides of the equation. g – 6 = 40 +6 g = 46 Example 2

8. Created by S. Koch - 2003 Solving a multiplication equation : 8n = 32 Get rid of the 8 by dividing both sides of the equation by 8. Here we undo multiplication by doing the opposite – division. 8n = 32 88 n = 4 Example 3

9. Created by S. Koch - 2003 Solving a division equation : k / 9 = 11 Get rid of the 9 by multiplying both sides of the equation by 9. Here we undo division by doing the opposite – multiplication. k / 9 = 11 x 9 k = 99 Example 4

10. Created by S. Koch - 2003 Homework Use your notes and show ALL steps.