2. Main Idea and New Vocabulary Example 1: Solve Two-Step Equations
Example 3: Equations with Negative Coefficients
Example 4: Combine Like Terms First
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3. Solve two-step equations.
Main Idea/Vocabulary

4. Solve Two-Step Equations
Solve 5y + 1 = 26.
Method 1 Use a model.
Remove one 1-tile from each mat.
Example 1

5. Solve Two-Step Equations
Separate the remaining tiles into 5 equal groups.
There are five 1-tiles in each group, so y = 5.
Example 1

6. Solve Two-Step Equations
Method 2 Use symbols.
Use the Subtraction Property of Equality.
5y + 1 = 26 Write the equation.
– 1 = – 1 Subtraction Property of Equality
5y = 25
Example 1

7. Solve Two-Step Equations
Use the Division Property of Equality.
5y = 25
y = 5 Simplify.
Division Property of Equality
Answer: The solution is 5.
Example 1

8. Solve 4b – 3 = 17.
A. 3.5
B. 5
C. 14
D. 20
Example 1 CYP

9. Solve Two-Step Equations
Write the equation.
– 2 = – 2 Subtraction Property of Equality
Simplify.
3 • (–6) = 3 • Multiplication Property of Equality
–18 = z
Answer: The solution is –18.
Example 2

10. Solve h + 12 = 8. __ 1 5
A. –20
B. –4
C. 28
D. 100
Example 2 CYP

11. Equations with Negative Coefficients
Solve 8 – 3x = 14.
8 – 3x = 14 Write the equation.
8 + (–3x) = 14 Rewrite the left side as addition.
– 8 = – 8 Subtraction Property of Equality
–3x = 6 Simplify.
Division Property of Equality
x = –2 Simplify.
Answer: The solution is –2.
Example 3

12.  Equations with Negative Coefficients Check Write the equation.?
Replace x with –2. ?
Multiply. ?
To subtract a negative number, add its opposite. 
The sentence is true.
Example 3

13. Solve 9 = 11 – 2y.
A. –10
B. –2
C. –1
D. 1
Example 3 CYP

14. Combine Like Terms First
Solve 14 = –k + 3k – 2. Check your solution.
14 = –k + 3k – 2 Write the equation.
14 = –1k + 3k – 2 Identity Property; k = 1k
14 = 2k – 2 Combine like terms; –1k + 3k = (–1 + 3)k or 2k
+ 2 = Addition Property of Equality
16 = 2k Simplify.
Division Property of Equality
8 = k Simplify.
Answer: The solution is 8.
Example 4

15.  Combine Like Terms First Check Write the equation. Replace k with 8.?
Replace k with 8. ?
Multiply. 
The statement is true.
Example 4

16. Solve 4w + 6 – 7w = 15.
A. –7
B. –3
C. 3
D. 9
Example 4 CYP