Write x^2 - 6x +7 in the form (x+a)^2 +b

Follow standard procedure that can be taught on a whiteboard. In general:ax^2 + bx + c = (x+b/2)^2 - (b/2)^2 + csox^2 - 6x + 7 = (x-3)^2 - (9) + 7= (x-3)^2 - 2