Algebra Overview

Jul 18, 2024

Algebra Overview 📊

Like Terms

  • Like terms: have the same variable part
  • Ex: 5x + 4x5x, 4x are like terms → 5x + 4x = 9x
  • Combine coefficients of like terms:
    • 3x + 4y + 5x + 8y8x + 12y

Combining Radicals

  • Radicals: Like terms must have the same radicand:
    • 3√2 + 8√2 + 5√7 + 3√711√2 + 8√7

Polynomial Operations

  • Use properties to combine or distribute terms
  • Addition/Subtraction:
    • Add/subtract coefficients of like terms
    • Ex: 7x + 4x^2 + 5x + 9x^213x^2 + 12x
    • Distribute negative signs
  • Multiplication: Distribute each term
    • Ex: monomial x trinomial: 7x * (x² + 2x - 3)7x³ + 14x² - 21x
    • Ex: binomial x binomial: 3x - 4 * 2x + 7 → Apply FOIL method: 6x² + 13x - 28
    • Ex: binomial x trinomial: Distribute each term in the binomial across the trinomial

Properties of Exponents

  • Multiplication: Add exponents
    • x³ * x⁴ = x⁷
  • Division: Subtract exponents
    • x⁹ / x⁴ = x⁵
  • Power of a Power: Multiply exponents
    • (x²)³ = x⁶
  • Negative Exponents: Move base to the opposite part of the fraction
    • x^(-3) = 1/x³

Simplifying Expressions:

  • Apply multiplication, power rules, and combine like terms
    • Ex: (3x³y⁻²)(7x⁻⁸y⁵)(21x⁻⁵y³) which becomes 21y³/x⁵

Solving Equations

  • Linear equations:
    • Isolate x: Ex: 2x + 4 = 9x = 2.5
    • Combine like terms, move constants to one side, divide to solve for x
  • Quadratic equations (factoring, quadratic formula):
    • Factoring: ax² + bx + c = 0
    • Quadratic Formula: x = [-b ± √(b² - 4ac)] / (2a)
    • Complete the square method for non-factorable cases

Graphing Linear Equations

  • y = mx + b form: m = slope, b = y-intercept
  • Plot y-intercept, use slope to find another point
  • Standard Form: Ax + By = C
    • Convert to slope-intercept for graphing: y = mx + b

Writing Equations of Lines

  • Given a point & slope: Use point-slope form
    • y - y1 = m(x - x1)
    • Convert to slope-intercept: y = mx + b
  • Given 2 points: Find slope, use point-slope form
    • m = (y2 - y1) / (x2 - x1)

Parallel and Perpendicular Lines

  • Parallel lines: Same slope
  • Perpendicular lines: Negative reciprocal slopes (if m1 = a/b, m2 = -b/a)

Practice Problems

  • Many practice problems given to apply and test understanding of each section.