Python program to create quadratic Equation

from math import sqrt x = float(input("Insert x = ")) y = float(input("Insert y = ")) z = float(input("Insert z = ")) a = y*y-4*x*z if a>0: x1 = (-y + sqrt(a))/(2*x) x2 = (-y - sqrt(a))/(2*x) print("x1 = %.2f; x2 = %.2f" % (x1,x2)) elif a==0: x1 = -y/(2*x) print("x1 = %.2f" % x1) else: print("No roots exist")