[correct answer receives brainliest only
the work of a student to solve a set of equations is shown: equation a: y = 16 – 2z equation b: 7y = 2 – 4z

step 1: –7(y) = –7(16 – 2z) [equation a is multiplied by –7.]
7y = 2 – 4z [equation b]
step 2: –7y = 16 – 2z [equation a in step 1 is simplified.]
7y = 2 – 4z [equation b]
step 3: 0 = 18 – 6z [equations in step 2 are added.]
step 4: 6z = 18
step 5: z = 3

in which step did the student first make an error?

step 3
step 4
step 1
step 2