Divide. `(x^2 - 81)/(x^2 -5 x - 36)-:(5 x)/(x + 4)`

State the quotient in simplest form.

`(x^2 - 81)/(x^2 -5 x - 36)-:(5 x)/(x + 4)=`

Enter the numerator and denominator separately in the boxes above. If the denominator is 1, enter the number 1. Do not leave either box blank.