The work of a student to solve a set of equations is shown:


Equation A: y = 4 − 2z

Equation B: 4y = 2 − 4z





Step 1:

−4(y) = −4(4 − 2z) [Equation A is multiplied by −4.]

4y = 2 − 4z [Equation B]



Step 2:

−4y = 4 − 2z [Equation A in Step 1 is simplified.]

4y = 2 − 4z [Equation B]



Step 3:

0 = 6 − 6z [Equations in Step 2 are added.]



Step 4:

6z = 6



Step 5:

z = 1



In which step did the student first make an error?


Step 1


Step 3


Step 4


Step 2