Algebra 1 · Chapter 2 of 8

Linear Equations and Inequalities

Solve one-variable equations and inequalities, including fractions, parentheses, variables on both sides, and real constraints.

Why this chapter matters

Linear equations describe break-even points, missing measurements, rates, and many other situations where one unknown must be found.

What you will learn

  • Solve multi-step equations and verify solutions by substitution.
  • Recognize equations with one, none, or infinitely many solutions.
  • Solve and graph inequalities while handling negative multiplication correctly.

Lessons in this chapter

  1. Solving linear equationsUse inverse operations and preserve equality at every step. Read the full guide →
  2. Variables on both sidesCollect variable terms and diagnose identities or contradictions.
  3. Solving inequalitiesReverse the inequality when multiplying or dividing by a negative value. Read the full guide →
  4. Modeling constraintsTranslate limits such as budgets and capacities into inequalities.

Study task

Model a $120 event budget with a $30 room fee and $8 per guest. Find and graph the possible number of guests.

Chapter checkpoint

Solve 4(x - 2) + 3 = 2x + 9.

Expand to 4x - 5 = 2x + 9, subtract 2x, add 5, and get 2x = 14, so x = 7.