The work of a student to solve the equation 3(2x − 4) = 8 + 2x + 6 is shown below: Step 1: 3(2x − 4) = 8 + 2x + 6 Step 2: 5x − 7 = 14 + 2x Step 3: 5x − 2x = 14 + 7 Step 4: 3x = 21 Step 5: x = 7 In which step did the student first make an error and what is the correct step? (5 points) a Step 2; 6x − 12 = 14 + 2x b Step 2; 6x − 7 = 2(6 + x + 4) c Step 3; 5x − 2x = 14 − 7 d Step 3; 5x + 2x = 14 + 7