Answer:
21x - 9
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Distributive Property
Algebra I
Explanation:
Step 1: Define
18x - (-3x + 9)
Step 2: Simplify
- Distribute negative: 18 + 3x - 9
- Combine like terms: 21x - 9