Equations and systems of equations

# systems of linear equations

There are methods to convert a system of equations into an equation with just one unknown. You can solve it graphically, too.

The main methods to solve linear systems are:

–The graph method

–The substitution method

–The algebraic equation method

–The elimination method

**graph method**

You have to draw the two lines and find the intersection point.

Example :

**substitution method**

You have to work out one unknown in one equation and substitute it in the other.

Example 1:

Example 2:

**algebraic equation method**

You have to work out one unknown in both equations and equalize.

Example 1:

Example 2:

**elimination method**

You have to remove one unknown in one equation by combining the two equations.

Example 1:

Example 2:

**Exercise**. Solve the following systems by using the four methods:

You can check the solutions by using this application:

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