How do you solve the system #17x - y + 2z = -9#, #x + y - 4z = 8#, #3x - 2y - 12z = 24#?
These are three linear equations in three variables. To solve them pick two equations and eliminate one variable and then choose another two equations and eliminate the same variable again. This will give us two linear equations in two variables, which can then be solved. The process in case of these equations could be as follows:
Adding first two equations, we can eliminate
We can also eliminate in second and third equation by adding double of second equation in third equation, as follows.
Putting this in equation (B) we get
Putting values in
Hence solution is