Form of the parabola:
Standard form:
y = ax² + bx + c
Vertex form:
y = a(x-h)² + k
The vertex is a point, V(h,k), on the parabola. Where:
h = -b/(2a) ; k = (4ac-b²)/4a
If the vertex point is :
V(h,k) = (-2.5, -6.25)
the equation of this function in vertex form is:
y = a(x - (-2.5))² + (-6.25)
y = a(x + 2.5)² - 6.25