A student is solving the system of equations below. In which line is a mistake first made?
2x + y - 2z = 23
3x + 2y + z = 11
x - y + z = -2
Line 1 z = 11 + 3x + 2y
Line 2 2x + y - 2(11 + 3x + 2y) = 23
Line 3 -4x - 3y = 45
Line 4 x - y + (11 + 3x + 2y) = - 2
Line 5 4x + y = - 13
Line 6 -2y = 32
Line 7 y = 16, x = ¾, z = -11/4
