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๐Ÿ”ŸElementary Algebra Unit 2 Review

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2.3 Solve Equations with Variables and Constants on Both Sides

๐Ÿ”ŸElementary Algebra
Unit 2 Review

2.3 Solve Equations with Variables and Constants on Both Sides

Written by the Fiveable Content Team โ€ข Last updated September 2025
Written by the Fiveable Content Team โ€ข Last updated September 2025

Solving equations with variables and constants on both sides is a crucial skill in algebra. It involves isolating variables, combining like terms, and performing inverse operations to find solutions.

These techniques are essential for more complex problem-solving in math and science. By mastering these skills, you'll be able to tackle a wide range of equations and real-world applications with confidence.

Solving Equations with Variables and Constants on Both Sides

Equations with constants on both sides

  • Isolate variable term on one side by performing same operation on both sides to maintain equality
    • Add or subtract same value from both sides (3x + 5 = 2x + 8 โ†’ 3x + 5 - 2x = 8)
    • Multiply or divide both sides by same non-zero value (2x/3 = 4 โ†’ 2x = 12)
  • Simplify equation by combining like terms on each side (3x - 2x = x)
  • Isolate variable by performing inverse operation on constant term
    • If constant added or subtracted, do opposite (x + 5 = 8 โ†’ x = 8 - 5 = 3)
    • If constant multiplied or divided, do reciprocal (2x = 10 โ†’ x = 10/2 = 5)

Balancing equations with variables

  • Identify variable terms on both sides (4x + 3 = 2x - 7)
  • Determine operation to isolate variables on one side
    • If same sign, subtract one side from both (4x - 2x + 3 = -7)
    • If opposite signs, add both sides (3x + 2 = -2x + 9 โ†’ 5x + 2 = 9)
  • Perform chosen operation on both sides to maintain equality (2x + 3 = -7)
  • Simplify by combining like terms on each side (2x = -10)
  • Isolate variable by performing inverse operation on remaining terms (x = -5)

Solving complex algebraic equations

  1. Identify variable and constant terms on both sides ($3x - 2 = 5x + 7$)

  2. Determine goal of manipulation

    • Isolate variable on one side ($3x - 5x = 7 + 2$)
    • Eliminate variable on one side ($4x - 1 = 3(x + 2) โ†’ 4x - 1 = 3x + 6$)
  3. Perform same operation on both sides to maintain equality ($-2x = 9$)

  4. Simplify by combining like terms on each side ($x - 1 = 6$)

  5. Repeat performing operations and simplifying until variable isolated or eliminated ($x = 7$)

  6. Solve for variable by performing inverse operation on remaining terms

    • If variable has coefficient, divide both sides by coefficient ($2x = 14 โ†’ x = 7$)

Equation Solving Strategies and Concepts

  • Utilize algebraic expressions to represent relationships between variables and constants
  • Apply transposition to move terms from one side of the equation to the other
  • Implement various equation solving strategies to efficiently isolate variables
  • Determine the solution set, which includes all possible values that satisfy the equation