Question

Soe x+y-2z=5 -x+2y+z=2 2x+3y-z=9

Answer 1

Answer:

x=1

y=2

z=-1

Step-by-step explanation:

Add the first two equations: (this will be equation 4)

$3y - z = 7$

Multiply the first equation by 2:

$2x + 2y - 4z = 10$

Take the third equation and subtract the above equation.

$y + 3z = - 1$

Multiply that by 3:

$3y + 9z = - 3$

Subtract equation 4:

$10z = - 10$

$z = - 1$

For y+3z=-1, plug in values:

$y + 3( - 1) = - 1$

$y - 3 = - 1$

$y = 2$

Plug in y and z values in first equation:

$x + 2 - 2( - 1) = 5$

$x + 2 + 2 = 5$

$x = 1$