Help on this exponential/logarithmic problem

E^y +3
------------- = k
E^y + 7

Solve for y, thanks for any help!

(e^y + 3)/(e^y + 7) = k
ke^y + 7k = e^y + 3
ke^y - e^y = 3 - 7k
e^y(k - 1) = 3 - 7k
e^y = (3 - 7k)/(k - 1)
ln[e^y] = ln[(3 - 7k)/(k - 1)]
y = ln(3 - 7k) - ln(k - 1)