Python program to Quadratic Equations with Solutions at Specified Range of Coefficient

import math
x1 = int(input("Insert the value of x1: "))
x2 = int(input("Insert the value of x2: "))
y1 = int(input("Insert the value of y1: "))
y2 = int(input("Insert the value of y2: "))
z1 = int(input("Insert the value of z1: "))
z2 = int(input("Insert the value of z2: "))
x = range(x1, x2+1)
y = range(y1, y2+1)
z = range(z1, z2+1)
for i in x:
 if i == 0:
  continue
 for j in y:
  for k in z:
   print(i, j, k, end=' ')
   A = j*j-4*i*k
   if A >= 0:
    x1 = (-j - math.sqrt(A))/(2*i)
    x2 = (-j + math.sqrt(A))/(2*i)
    print("Valid", round(x1,2), round(x2,2))
   else:
    print("Invalid")

Insert the value of x1: 1
Insert the value of x2: 1
Insert the value of y1: 1
Insert the value of y2: 1
Insert the value of z1: 1
Insert the value of z2: 1
1 1 1 Invalid

Insert the value of x1: -1
Insert the value of x2: -1
Insert the value of y1: 1
Insert the value of y2: 1
Insert the value of z1: 1
Insert the value of z2: 1
-1 1 1 Valid 1.62 -0.62