7x - 3y = 4 2x - 4y = 1 which of the following system of equations is not equal to the system of equations shown above?

This is the system given by you: a) 7x - 3y = 4 and b) 2x - 4y = 1

I will compare it with these three systems:

1) -28x + 12 = -16 and 28x - 56y = 14

You can check that if you mulitply the equation a) times - 4 and the equation b) times  -14, you get the equations of this new system. Then the two systems are equal.

2)  28x  - 12y = 16 and -6x + 12y = - 3

You can check that if you multiply the equation a) times 4 and the equation b) times - 3 you get the same equations of this system, then the two systems are equals.

3) 14x - 6y = 4 and -14x + 28y = 1

You can check that these equations cannot not be obtained from a) and b) then the systems are different.

You can solve both systems and you will obtaind different values for the xs and the ys.