You can put this solution on YOUR website!
multiply equation by (n-9), cancel the denominators, and you have
n + 4(n-9) = n
subtract n from both sides
4(n-9) = 0
4n - 36 = 0
4n = 36
n = 36/4
n = 9, but this cannot be the solution, (division by 0), therefore,
There is no solution.