Skip to content
Homework Help

Solving Systems of Equations: Substitution vs Elimination

Two core methods for simultaneous equations, when to use each, and what no solution or infinitely many solutions look like.

By AI Math Solver Team · · 6 min read

A system of equations asks for values that satisfy every equation at once.

Substitution

Solve one equation for a variable, substitute into the other.

Best when a variable already has coefficient 1.

Elimination

Add or subtract equations to cancel a variable.

Multiply the second equation by 3 and add: , so , .

Special cases

  • No solution: you reach a false statement like (parallel lines).
  • Infinitely many: you reach (the same line twice).

Check your work with the System of Equations Calculator.

#systems of equations#elimination#substitution

Practice what you just learned

Solve your own problems step by step and ask the AI tutor about anything that's unclear.