SOLUTION: I have no clue how to do this. Can you please work it out for me. x+2y-3z=2 3y- z=13 3y+5z=25 Thank you so much. Janet

Algebra ->  Linear-equations -> SOLUTION: I have no clue how to do this. Can you please work it out for me. x+2y-3z=2 3y- z=13 3y+5z=25 Thank you so much. Janet      Log On


   

Question 235545: I have no clue how to do this. Can you please work it out for me.
x+2y-3z=2
3y- z=13
3y+5z=25
Thank you so much.
Janet
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
x + 2y - 3z = 2
3y - z = 13
3y + 5z =25
:
Start by subtracting the 2nd equation from the 3rd equation
3y + 5z = 25
3y - z = 13
--------------subtraction eliminates y, find z
6z = 12
z = 12%2F6
z = 2
;
Find y using the 2rd equation, substitute 2 for z
3y - 2 = 13
3y = 13 + 2
3y = 15
y = 5
;
find x using the 1st equation, substituting for y and z
x + 2(5) - 3(2) = 2
x + 10 - 6 = 2
x + 4 = 2
x = 2 - 4
x = -2