The following is an example of a student's work to solve the equation 2(6y 3) = 20 + 6y:
Step 1: 2(6y − 3) = 20 + 6y
Step 2: 8y − 5 = 20 + 6y
Step 3: 2y − 5 = 20
Step 4: 2y = 25
Step 5: y = 12.5
What step did the student make the first mistake on, and what is the correct step?
A Step 2: 8y − 5 = 10 + 3y
B Step 2: 12y − 6 = 20 + 6y
C Step 3: 6y − 3 = 2(18 + 3y)
D Step 3: 2(6y − 3) = 18 + 3y
