When parabola Equation Vertex: (h, k), Focal point: (x1, y1), parabola vertex (geometry) Equation:

(X-h)² = 4a(Y-k);     ( a = √(h-x1) * (h-x1) + (k - y1) * (k-y1) )

parabola Equation Standard formality:

Y = X a quarter (a) ² - (h / 2 a) + X (k + h ² / 4 a); ( a = √(h-x1) * (h-x1) + (k - y1) * (k-y1) )