Question

7. What is the value of z in the solution to the systems of linear equations shown below?

-x+ 2y + 2z= -4
4x +y-3z=13
x- 5y +z = -23

Answer 1

Explanation:

`1) \: \: - x + 2y + 2z = - 4 \\ 2z = - 4 + x - 2y \\ z = ( - 4 + x - 2y)/(2) \\ \\ 2) \: \: 4x + y - 3z = 13 \\ - 3z = 13 - 4x - y \\ z = (13 - 4x - y)/( - 3) \\ \\ 3) \: \: x - 5y + z = - 23 \\ z = - 23 - x + 5y \\`