Solve the following system of equations by using either substitution or elimination.
x + 2y + 7z = 54.35
5x -3y + 2z = 46.6
12x -24y –z = -40.95
x + 2y + 7z = 54.35
5x -3y + 2z = 46.6
12x -24y –z = -40.95