following expression represents the value of which variable in the solution of the following system of equations
-x+2y+7z=13
2x-y-2z=-2
3x+5y+2z=-14

options:
x
y
x
none of the variables
(explain answer)

following expression represents the value of which variable in the solution of the following system of equations x2y7z13 2xy2z2 3x5y2z14 options x y x none of t class=