jika g(x)=3x+5; f(x)=2x+4/x-3 (x tdk sama dgn 3) dan (gof)(k)=7, maka tentukan nilai k !

g(x) = 3x + 5

f(x) = (2x + 4)/(x - 3)

g(f(k)) = 7
3(2k + 4)/(k - 3) + 5 = 7
6k + 12 = (7 - 5)(k - 3)
6k - 2k = -12 - 6
4k = -18
k = -18/4
k = -9/2