Question

If you were to use the substitution method to solve the following system, choose the new system of equations that would result if x was isolated in the first equation.

x + 6y + z = 2
x – 3y + 2z = –1
x + 5y + 3z = –4

Answer 1

x= 2-z-6y
2nd equation becomes:
(2-z-6y)-3y+2z = -1 or -9y+z=-3
3rd equation becomes:
(2-z-6y)+5y+3z=-4 or -y+2z =-6