Answer :
(g-f)(x)=g(x)=f(x)
(g-f)(x)=6x-4+x^2
(g-f)(x)=x^2+6x-4 then:
(g-f)(3)=3^2+6*3-4
(g-f)(3)=9+18-4
(g-f)(x)=23
(g-f)(x)=6x-4+x^2
(g-f)(x)=x^2+6x-4 then:
(g-f)(3)=3^2+6*3-4
(g-f)(3)=9+18-4
(g-f)(x)=23