Jess tried to solve the equation 2x + 2 = 12. She wrote down the steps as shown below. She made the first mistake in

 
2x + 2 = 16 + x

 
Step 1: 2x + x = 16 + 2
Step 2: 3x = 18 
Step 3: x = 18 ÷ 3
Step 4: x = 6