1. Fundamental Concepts
- Definition: Equations with variables on both sides are algebraic equations where the variable appears on both the left and right sides of the equation.
- Objective: The goal is to isolate the variable on one side of the equation.
- Steps: Typically involves combining like terms, using inverse operations, and simplifying expressions.
2. Key Concepts
Basic Rule: $$4x + 3 = 2x - 5$$
Degree Preservation: The highest degree in the result matches input
Application: Used to solve real-world problems involving multiple unknowns
3. Examples
Example 1 (Basic)
Problem: Solve $$3x + 4 = 2x - 7$$
Step-by-Step Solution:
- Subtract \(2x\) from both sides: $$3x - 2x + 4 = -7$$
- Simplify: $$x + 4 = -7$$
- Subtract 4 from both sides: $$x = -11$$
Validation: Substitute \(x = -11\): Original: \(3(-11) + 4 = 2(-11) - 7 \rightarrow -33 + 4 = -22 - 7 \rightarrow -29 = -29\) ✓
Example 2 (Intermediate)
Problem: $$5y - 3 = 2y + 8$$
Step-by-Step Solution:
- Subtract \(2y\) from both sides: $$5y - 2y - 3 = 8$$
- Simplify: $$3y - 3 = 8$$
- Add 3 to both sides: $$3y = 11$$
- Divide by 3: $$y = \frac{11}{3}$$
Validation: Substitute \(y = \frac{11}{3}\): Original: \(5(\frac{11}{3}) - 3 = 2(\frac{11}{3}) + 8 \rightarrow \frac{55}{3} - 3 = \frac{22}{3} + 8 \rightarrow \frac{55}{3} - \frac{9}{3} = \frac{22}{3} + \frac{24}{3} \rightarrow \frac{46}{3} = \frac{46}{3}\) ✓
4. Problem-Solving Techniques
- Visual Strategy: Use a balance scale analogy to visualize moving terms across the equal sign.
- Error-Proofing: Double-check each step by substituting the solution back into the original equation.
- Concept Reinforcement: Practice with a variety of problems that involve different types of coefficients and constants.