,

Subtract from .

Add and .

Write the system of equations in matrix form.

Perform the row operation on (row ) in order to convert some elements in the row to .

Replace (row ) with the row operation in order to convert some elements in the row to the desired value .

Replace (row ) with the actual values of the elements for the row operation .

Simplify (row ).

Perform the row operation on (row ) in order to convert some elements in the row to .

Replace (row ) with the row operation in order to convert some elements in the row to the desired value .

Replace (row ) with the actual values of the elements for the row operation .

Simplify (row ).

Use the result matrix to declare the final solutions to the system of equations.

Multiply both sides of the equation by .

Multiply by .

The solution is the set of ordered pairs that makes the system true.

Solve Using an Augmented Matrix 5x-6x=-7 , -15x+18x=21