Question 1103713
if you can eliminate one of the variables, then you might be able to solve using two dimensional graphing software for two of the variables.


after that, it's a simple matter to solve for the third.


it's probably best to eliminate the z if you can because most two dimensional graphing software work with x and y only.


your equations are:


x + y + z = 6 (equation 1)
x - y + z = 2 (equation 2)
2x + 3y - z = 5 equation 3)


add equation 1 to equation 3 to get:


3x + 4y = 11 (equation 4)


subtract equation 2 from equation 1 to get:


2y = 4 (equation 5)


equations 4 and 5 can be graphed to find their intersection.


the intersection of those 2 equations on the graph is (1,2).


that means that x = 1 and y = 2


use those values for y and go back to any of the original equations to find that z = 3.


all original equations are true when x = 1 and y = 2 and z = 3, confirming that the solution is correct.


here's the graph of equations 4 and 5.


those equations are:


3x + 4y = 11 (equation 4)
2y = 4 (equation 5)


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