Right so, I actually know the math, my problem is that I think, I am getting confused with wording. I will explain better where I show you where my problem lies. Question: Show that [itex]2x^2-36x+175[/itex] mat be written in [itex]a(x-b)+c[/itex] where the values a,b,c are to be found. state, with reason, the least possible value of [itex]2x^2-36x+175[/itex] so basically I complete the square, I get [itex]2(x-9)+26[/itex] the book ans [itex]1(x-9)+13[/itex] so all they have done is not multiplied back through by 2. The when it comes to find the least possible value x=9 and y= 13. I did check this with differentiation and get x=9 which don't get me wrong I can see that, but what I don't understand, my books when ever completing the square always multiply through with the number factored out. This has cause some confusion on my part.