Answer :

( fog )(x) = f(g(x)) =3*g(x) - 1 = 3(2x+5) -1 = 6x + 15 - 1 = 6x + 14;
( gof )(x) = g(f(x)) = 2 *f(x) + 5 =2(3x-1) + 5 = 6x-2 + 5 = 6x + 3 ;
( fog )(-2) = 6*(-2) +14 = -12 + 14 = 2;
( gof )(-2) = 6*(-2) + 3 = -12 + 3 = - 9.