Ernesto tried to determine the solution for the system of equations using substitution. His work is shown below.
 x – y = 7
 3x – 2y = 8
 Step 1: x = y + 7
 Step 2: 3(y + 7) – 2y = 8
 Step 3: 3y + 7 – 2y = 8
 Step 4: y + 7 = 8
 Step 5: y = 1
 In which step did Ernesto make the first error?
 Step 1
 Step 2
 Step 3
 Step 4