Assuming the given equation is (x-2)^2 = 9, Edna is partially correct. Saying x-2 = 3 is halfway there in terms of getting the ful solution. She forgot about the minus form of the plus minus. If (x-2)^2 = 9, then applying the square root to both sides leads to these two equations: x-2 = 3 or x-2 = -3. So we have a plus 3 and then a minus 3.