C-05-Q132mediumsingle_mcqIf f(x)=x2−6x+15f(x) = x^2 - 6x + 15f(x)=x2−6x+15 and f(x)=7f(x) = 7f(x)=7, the values of xxx are —a2, 42,\ 42, 4b3, 53,\ 53, 5c−2, −4-2,\ -4