Respuesta :

y = x^2 - 6x + 14
y = x^2 - 2 . (x) . (3)  + 9 + 5 ....... (using  (a-b)^2 = a^2 -2ab+b^2) 
y = (x - 3)^2 + 5 ...this is your answer
divide the coefficient of  x by 2  -6 / 2 = -3;

y = (x - 3)^2  + k
y = (x - 3)^2 - 9 + 14
y = (x-3)^2 + 5   is ur answer