AlgèbreFacile
Math Learning PlatformSystems of Equations
Advanced
📚 equations
📖 About this lesson
Solve systems of linear equations with multiple methods
Lesson Content
Systems of Linear Equations
💡 Tip
A system of equations contains multiple equations to solve simultaneously.
Substitution method
- •Isolate one variable in one equation
- •Substitute in the other equation
- •Solve to find first variable
- •Substitute to find second
Elimination method
- Multiply equations to equalize coefficients
- Add or subtract to eliminate variable
- •Solve obtained equation
- •Substitute to find other variable
Graphical method
Solutions are intersection points of lines.
Special cases
- •[object Object],: unique solution
- •[object Object],: no solution (parallel lines)
- •[object Object],: infinite solutions (coincident lines)
Practical Examples
1
Example 1
📋 Problem
Résoudre : 2x + y = 7 et x - y = 2
✅ Solution
x = 3, y = 1
💡 Explanation
Addition des équations : 3x = 9, donc x = 3. Substitution : 2(3) + y = 7, donc y = 1