The equation used to find the parabola’s vertex’s x coordinate
-(b/2a)
Quadratic formula
x = (-b±√ b^2-4ac)/2
Circle area formula
A=πr^2
Circle circumference
C=2πr
Circle Coordinate equation
(x-h)^2 + (y-k)^2 = r^2
https://www.gstatic.com/education/formulas2/472522532/en/equation_of_a_c