8Substitution method
In the first part of the introductory course you have already learned how to set up a system of linear equations (LGS) and solve it with the equation method.
However, there are also other methods to solve a LGS!
The substitution method is very similar to the elimination by equation.
Why do we use it?
Quite simply, it is less work than the equation method!
How does it work?
The substitution method works like this:
Solve only one of the two equations by one of the two variables.
Substitute the variable you solved for into the other of the two equations.
You get a value, which you again insert into one of the equations. This already gives you the solution.
Sounds complicated? Actually, it is not! This is how it looks:
