I would explain on the whiteboard how to factorise itleading them to having two brackets, (x + 3) and (x+3). Could also be written as (x+3)^2then teach them on whiteboard how to solve the equation(x+3)^2 = 0hence x+3 = 0hence x = -3OR-(x+3) = 0-x -3 = 0x + 3 = 0so again, x = -3So, the solution is x = -3would use whiteboard to explain all this