1. Solving 1 and 2 Step Equations
Dr. Fowler  CCM
Solving 1 and 2 Step Equations

2. Watch Equations Video

3. Equations Video

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

5. We need to get the “x” ALONE!
Identify which number is with the “x”.
Which operation ( +, -, x,  ) is attaching the number to the “x”?
Use the Opposite Operation to remove the number.
Opposites Rule – to get rid of a term from either side of an equation, just do the opposite operation.

6. Solving one-step equations:
To undo an operation, use the OPPOSITE OPERATION – –
x ÷
÷ x

7. Solving an addition equation: t + 7 = 21
Example 1
Solving an addition equation:
t + 7 = 21
Get rid of the 7 by subtracting 7 from both sides of the equation. -7 -7
t = 14

8. Solving a subtraction equation: g – 6 = 40
Example 2
Solving a subtraction equation:
g – 6 = 40
Get rid of the 6 by adding its opposite to both sides of the equation. +6 +6
g = 46

9. Solving a multiplication equation: 8n = 32
Example 3
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 8 8
n = 4

10. -3x = 21 x = -7 Solving a division equation: Example 4
Get rid of the -3 by Dividing both sides by -3.
“Undo” division with multiplication.
x = -7

11. Steps for Solving Two-Step Equations

12. 1) Solve 2x - 1 = -3 + 1 + 1 2x = -2 2 2 x = -1 2(-1) - 1 = -3
2x = -2
x = -1
2(-1) - 1 = -3
-2 – 1 = -3
Draw “the river”
Add 1 to both sides
Simplify
Divide both sides by 2
Check your answer

13. Try These Examples
2x – 5 = 17
3y + 7 = 25
5n – 2 = 38
12b + 4 = 28

14. Check your answers!!!
x = 11
y = 6
n = 8
b = 2

15. 2) Solve + 4 + 4 3 · · 3 x = 36 12 – 4 = 8 D U Draw “the river”
÷ 3
- 4
+ 4
· 3
3 · · 3
x = 36
12 – 4 = 8
Draw “the river”
Add 4 to both sides
Simplify
Clear the fraction -Multiply both sides by 3
Check your answer

16. 3) Solve d = 10 d – 4 = 6 + 4 + 4 D U Draw “the river”
- 4
÷ 2
· 2
+ 4
Draw “the river”
Clear the fraction - Multiply both sides by 2
Simplify
Add 4 to both sides
Check your answer
d – 4 = 6
d = 10

17. 4) Solve
d = -7
d = -19
d = -17
d = 17
Answer Now

18. 5) Solve -3 -3 a = 35 D U Draw “the river” Subtract 3 from both sides
÷ -7
+ 3
- 3
· -7
Do/Undo Chart – This one is tricky! Remember to always use the sign in front of the number.
a = 35
Draw “the river”
Subtract 3 from both sides
Simplify
Clear the fraction – Multiply both sides by -7
Check your answer