You are given the system of equations to solve by the elimination method, which is an incorrect step that will not produce a system with the same solution? a) multiply the first equation by 6 and subtract the second equation. b) multiply the first equation by -6 and add the second equation. c) multiply 3x by 6 in the first equation and subtract the second equation. d) add 2 times the first equation and -1/3 times the second equation.