Question 38046
Remember that negative exponents on top become positive exponents on the bottom and that negative exponents on bottom become positive on top.  Thus with
(24x^-4)(y^-9) / (8x^-7)(y^-1)
all of them shift postion (since they are all negative) and we get
24(x^7)(y) / 8(x^4)(y^9)
Now cancel where possible
3x^3 / y^8
and we're done