✩ f○g = f(g(x)) = g(x)+3 = x+4 + 3 = x+7
g○f = g(f(x)) = f(x)+4 = x+3 + 4 = x+7
✩ f○g = f(g(x)) = 2g(x)+6 = 2(3x-1) + 6 = 6x-2 + 6 = 6x+4
g○f = g(f(x)) = 3f(x)-1 = 3(2x+6) - 1 = 6x+18 - 1 = 6x+17
✩ f○g = f(g(x)) = g(x)+1 = x+2 + 1 = x+3
g○f = g(f(x)) = f(x) + 2 = x+1 + 2 = x+3
