To help the student understand how to expand the brackets I would start by splitting the equation to:3x2(x - 3) + 6x(x - 3) + 7(x - 3)I then would ask the student to expand these brackets to:3x3 - 9x2 + 6x2 - 18x + 7x - 21Then I would ask the student to collect the like terms and simplify the equation to:3x3 - 3x2 - 11x - 21