Chapter 9 - Section 9.1 - Solving Systems of Linear Equations in Three Variables and Problem Solving - Exercise Set - Page 641: 58

Answers may vary, based on the equations presented in the previous question. ${(x, y, z) | x+y+z=6}$

$x+y+z=6$ $-2x-2y-2z=-12$ $-3x-3y-3z=-18$ $-2x-2y-2z=-12$ $-2(x+y+z)=-2*6$ $-3x-3y-3z=-18$ $-3(x+y+z)=-3*6$ The three equations are the same: $x+y+z=6$. Thus, the solution set is ${(x, y, z) | x+y+z=6}$