SOLUTION: How Do you solve this Three-variable equation by substitution? {13=3x-y {4y-3x+2z=-3 {z=2x-4y

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Question 362519: How Do you solve this Three-variable equation by substitution?
{13=3x-y
{4y-3x+2z=-3
{z=2x-4y
Answer by HasanSahin(52) About Me  (Show Source):
You can put this solution on YOUR website!
+13=3x-y+++++
+4y-3x%2B2z=-3+
+z=2x-4y+++++
Put everything in order such that;
+13=+3x+-+y+++++
+-3=-3x+%2B4y+%2B2z+
++0=+2x+-4y+-z++
Multiply the third equation by 2 and you'll get;

+13=+3x+-+y+++++
+-3=-3x+%2B4y+%2B2z+
++0=+4x+-8y+-2z++
Sum up 2nd and 3rd equations and you'll get;
+13=+3x+-+y++
+-3=+x+-+4y++
Multiply the first equation by -4 and you'll get;

-52=-12x+%2B4y++
+-3=++x++-4y++
Sum up these equations and you'll get;

-55=-11x+
Then you get+x+=+5+; for example put "x" into "-3 = x -4y" equation,you'll get;
+y+=2+;for example if you put "y and x" into "0= 2x -4y -z" equation,you'll get;
+z=2+

RF.