How Do You Solve a System of Equations Using the Elimination by Subtraction Method?

How Do You Solve a System of Equations Using the Elimination by Subtraction Method?

Note:

There are many different ways to solve a system of linear equations. In this tutorial, you'll see how to solve such a system by combining the equations together in a way so that one of the variables is eliminated. Then, see how find the value of that variable and use it to find the value of the other variable. Take a look!

Keywords:

  • problem
  • line
  • linear equations
  • system of equations
  • system
  • 2 equations
  • find intersection
  • solve system of equations
  • solve by elimination
  • elimination
  • variable elimination
  • subtract equations
  • consistent
  • 1 solution
  • independent
  • 2 equations
  • 2 unknowns
  • 2 variables

Background Tutorials

  • Definitions of Systems

      • What's a System of Linear Equations?What's a System of Linear Equations?

      What's a System of Linear Equations?

      A system of equations is a set of equations with the same variables. If the equations are all linear, then you have a system of linear equations! To solve a system of equations, you need to figure out the variable values that solve all the equations involved. This tutorial will introduce you to these systems.

      • What's a Solution to a System of Linear Equations?What's a Solution to a System of Linear Equations?

      What's a Solution to a System of Linear Equations?

      If you have a system of equations that contains two equations with the same two unknown variables, then the solution to that system is the ordered pair that makes both equations true at the same time. Follow along as this tutorial uses an example to explain the solution to a system of equations!

  • Solving Systems of Equations

      • How Do You Solve a System of Equations by Graphing?How Do You Solve a System of Equations by Graphing?

      How Do You Solve a System of Equations by Graphing?

      There are many different ways to solve a system of linear equations. In this tutorial, you'll see how to solve a system of linear equations by graphing both lines and finding their intersection. Take a look!

      • How Do You Solve Two Equations with Two Variables?How Do You Solve Two Equations with Two Variables?

      How Do You Solve Two Equations with Two Variables?

      Trying to solve two equations each with the same two unknown variables? Take one of the equations and solve it for one of the variables. Then plug that into the other equation and solve for the variable. Plug that value into either equation to get the value for the other variable. This tutorial will take you through this process of substitution step-by-step!

  • Evaluating Expressions

      • What is a Variable?What is a Variable?

      What is a Variable?

      You can't do algebra without working with variables, but variables can be confusing. If you've ever wondered what variables are, then this tutorial is for you!

  • Solving Systems Using Elimination

      • How Do You Solve a System of Equations Using the Elimination by Addition Method?How Do You Solve a System of Equations Using the Elimination by Addition Method?

      How Do You Solve a System of Equations Using the Elimination by Addition Method?

      There are many different ways to solve a system of linear equations. In this tutorial, you'll see how to solve a system of linear equations by combining the equations together to eliminate one of the variables. Then, see how find the value of that variable and use it to find the value of the other variable. Take a look!

Further Exploration

  • Solving Systems Using Elimination