8th Grade Math

Systems of Equations

Learn Systems of Equations in 8th Grade Math from the production AIPH study guide.

Advanced Topics

In a nutshell: Systems of equations find where two equations are true at the same time.

## Solving Systems of Equations Sometimes, you have to solve two equations at once! A **system of equations** is a set of two or more equations with the same variables. The solution is the point where both equations are true at the same time. ### Methods for Solving - **Substitution**: Solve one equation for one variable, then substitute into the other. - **Elimination**: Add or subtract equations to eliminate one variable. - **Graphing**: Plot both equations on a graph and find their intersection. ### Real-Life Applications Systems of equations help with things like planning budgets or finding when two things will be equal (like two trains meeting). #### Tips - Check solutions by plugging values into both equations. - Organize your work to avoid mistakes.

y = mx + b

Examples

  • If \( x + y = 10 \) and \( x - y = 2 \), add to get \( 2x = 12 \), so \( x = 6 \), then \( y = 4 \).
  • Graph \( y = 2x \) and \( y = x + 3 \); they intersect at \( (3, 6) \).

Key terms

System of Equations
A set of equations with the same variables.
Elimination
A method for solving systems by adding or subtracting equations.