SOLUTION: I have to solve the system of equations which are 2x-4y+2z=16 -2x+5y+2z=-34 x-2y+2z=4 I have simplified the 3rd equation to x=2y-2z+4. i then put that into the first equation

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: I have to solve the system of equations which are 2x-4y+2z=16 -2x+5y+2z=-34 x-2y+2z=4 I have simplified the 3rd equation to x=2y-2z+4. i then put that into the first equation      Log On


   

Question 165447This question is from textbook HEATH Algebra 2 An itergrated Approach
: I have to solve the system of equations which are
2x-4y+2z=16
-2x+5y+2z=-34
x-2y+2z=4
I have simplified the 3rd equation to x=2y-2z+4. i then put that into the first equation and had 2(2y-2z=4)-4y+2z=16 to get z equals -4. my problem is finding the x and y variables. when i try to find them my y's and x's always cancel each other out. please help me. :) This question is from textbook HEATH Algebra 2 An itergrated Approach

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
substitute the z value into the 2nd and 3rd eqns

-2x+5y+2(-4)=-34 __ -2x+5y=-26

x-2y+2(-4)=4 __ x-2y=12 __ multiplying by 2 __ 2x-4y=24

adding the equations __ -2x+5y+2x-4y=-26+24 __ y=-2

substituting __ x-2(-2)=12 __ x=8