Something

# -*- coding:Utf-8 -*-

from Tkinter import *
from math import *

def equa2emeDegre(a, b, c):
	"Résout une équation du deuxième degré"	

	delta = (b * b) - (4* a * c )
	if (delta < 0):
		labelReponse.configure(text ="L'équation ne peut être résolue (Delta < 0)")
	elif (delta == 0):
		reponse = ( (-b) / (2 * a) )
		labelReponse.configure(text ="S = {" + reponse + "}")
	elif (delta > 0):
		racineDelta = sqrt(delta)		
		reponse1 =  ( (-b + racineDelta)/ (2 * a) )
		reponse2 =  ( (-b - racineDelta)/ ( 2 * a) )
		labelReponse.configure(text ="S = {" + reponse1 + ";" + reponse2 + "}")

fen = Tk()
fen.title("Résolutions d'équations de mes dos")

#widgets
a = Entry(fen, bg ="light yellow")
labelA = Label(fen, text ="x(au carré) + ")
b = Entry(fen, bg ="light yellow")
labelB = Label(fen, text ="x +")
c = Entry(fen, bg ="light yellow")
labelC = Label(fen, text=" = 0")
boutonResout = Button(fen, text="Résoudre", command =equa2emeDegre( a.get(), b.get(), c.get()))
labelReponse = Label(fen)

a.pack()
labelA.pack()
b.pack()
labelB.pack()
c.pack()
labelC.pack()
boutonResout.pack()
labelReponse.pack()

fen.mainloop()