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YoshiOokami
how to solve linear equation with three variables x + y + z = -5 -2x - y + z = -1 x - 2y - z= 0
easy get rid of your Z variables first add 1st equation to your 3rd equation then add 2nd equation to your 3rd equation this way you have 2 equations with x and y solve them like you would a regular x and y system Once you know x or y sub it into 2 of your equations, maybe 2nd and 3rd and solve for the remaining variables.
you could do a matrix on your calculator too :)
I just tried to explain this to someone and it took me like half an hour haha. I highly recommend watching this video. http://www.youtube.com/watch?v=woqq3Sls1d8 your options are 1)substitution 2)subtraction/elimination 3)row reducing an augmented matrix. I guess method 2 and 3 are the same thing. for a small system of equations I would use method 1, for a large one I could use method 3.
yes the matrix feature on the TI84 or TI83 is real easy to use