Function f and g are defined by f : x->ax+2 and g : x->bx+3

Function f and g are defined by f : x->ax+2 and g : x->bx+3 respectively. If (gof)(x)=(fog)(x), find: a. the relation between a and b b. the value of x if a=5 for which: (i) (fof)(x)=f(x), (ii) (gog)(x)=g(x).