Lin is solving this system of equations:  {6x−5y=343x+2y=8   She starts by rearranging the second equation to isolate the y  variable: y=4−1.5x . She then substituted the expression 4−1.5x  for y  in the first equation as shown:  Step 1:   6x−5(4−1.5x)=34 Step 2:   6x−20−7.5x=34 Step 3:   −1.5x=54 Step 4:   x=−36 Step 5:  y=4−1.5x Step 6:  y=4−1.5(−36) Step 7:  y=58 In which step did Lin write the equation that contained the error that caused the system to be solved incorrectly?