I just took -6 divided by 2 is -3 squared it and got 9 and if you wanted to factor this out we have x squared minus 6x plus 9 so what 2 numbers when you take their product you get 9 and when you add them together you get -6 well -3 and -3 so this is going to be x-3 times x-3 or you could think of it as x-3 squared so it is a perfect square trinomial