Question

every quadratic equation has one real root

Answer 1

delta = 0    real and equal                                                                                          delta > 0    real and distinct                                                                                       delta < 0    no real roots                                                                                               b2 -4ac is called discriminate..

Answer 2

Yes,for an example , x^2 - 2x + 4 = 0 the real root is - 2 and 4.If there are no real root,how we can calculate other root?Am I right?