Grade 8 Math: Systems of Linear Equations (Simultaneous Equations)


Systems of linear equations are also called simultaneous linear equations. In this topic, the student learns how to solve systems of linear equations in two or three variables. This series of six lessons first teaches the student how to solve two simultaneous linear equations. The student first sees the solutions graphed, which helps them visualize the solution. Then, they learn the substitution method for two variables. The elimination method for two variables is also taught, and finally, the student learns to solve systems of linear equations in three variables.

This series of lessons helps the student further their knowledge of equations.

This series of lessons helps the student further their knowledge on equations.


Systems of Linear Equations (Simultaneous Equations) : Graphing

In this lesson, the student learns how to graph a system of linear equations on the coordinate plane. They also learn that the solution to the system is the intersection of the two lines.


Systems of Linear Equations (Simultaneous Equations): Substitution

In this lesson, the student learns the substitution method to solving a system of linear equations in two variables. The lesson shows the student how solving an equation for one variable gives you a value for that variable that can replace the variable in the second equation.


Systems of Linear Equations (Simultaneous Equations): Elimination I

In this lesson, the student learns that adding two equations together can eliminate one variable in a system of linear equations.


Systems of Linear Equations (Simultaneous Equations): Elimination II

In this lesson, the student learns how to eliminate a variable from a system of linear equations in two variables. The student learns how to determine which variable to eliminate and is shown how to determine which value to multiply the equations by in order to eliminate a variable.


Systems of Linear Equations in Three Variables – Substitution I

In this lesson, the student learns how to solve systems of linear equations with three variables. The student learns how to use the substitution method to solve a system of equations when one of the variables is already isolated.


Systems of Linear Equations in Three Variables – Substitution II

This lesson teaches the student how to solve systems of linear equations in three variables using the substitution method when no variable is isolated to begin with.



« Back to Math Topics by Grade Level