Algebra 1 · Systems of Equations & Inequalities
Substitution Method
Algebra 1 · Systems of Equations & Inequalities
Definition
The substitution method solves a system by replacing one variable with an equivalent expression from the other equation.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- From y = x + 1, substitute into 2x + y = 7.
- Solve one equation for a variable, then plug it in.
Key rule
Substitute to reduce the system to one equation in one variable.
Memory hook
Substitute one variable, then solve what is left.