Tutorial: Solving Systems of Linear Equations in three Variables:

Basic Instructions:
1.) Get rid of one of the variables using linear combination.
2.) Use linear combination to reduce the new equations to solve both variables.
3.) Plug the two numbers in to get the last variable.


Hint: Number the 3 original Equations for Clarity.

Ex.:
Solve:

Try it:
Solve:

1) 12x + 6y + 7y = -35
7x - 5y - 6z = 200
x + y = -10


2) 7x - 3y + 4z = -14
8x + 2y - 24z = 18
6x - 10y + 8z = -24





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