Raul used the steps shown below to solve the equation. In which step did Raul make a mistake?5x-3(2x+7)=2x+9Step 1: 5x-6x-21=2x+9Step 2: -11x-21=2x+9Step 3: -12x=30Step 4: x=-30/12A. Step 1B. Step 2C. Step 3D. Step 4