Question

how do i change x^2-8x = M to a vertex form to find where the minimum occurs at, i guess the x and y. :D

Answer 1

Well, you need to complete the square to get it into a form where you can easily spot the vertex.
y=x^2-8x
y=x^2-8x+16-16
y=(x-4)^2-16
So your vertex is (4,-16)