I'll assume it's y = 5x<sup>2</sup> - 5x.
Do you know any calculus? If so, find x when y' = 0.
If not, put it into the form by completing the square: y = a(x - b)<sup>2</sup> + c
a = the sign tells you if the parabola opens upwards (positive) or downwards (negative)
b = tells you how much and which way the parabola is horizontally shifted from y = x<sup>2</sup>
c = tells you how much and which way the parabola is VERTICALLY shifted
I'm Hoping you recognize that form.
Or you can use this formula for the parabola ax<sup>2</sup> + bx + c:
x<sub>vertex</sub> = -b/2a
