Question 164625
(6t^-7)/ (2t^9)


(6t^-7)=(6/t^7)*(1/2t^9)=3t^-16 

You can divde 6 by 2 and get 3 and add the negative exponents together to get -16

3/t^7+t^9=3/t^16=3t^-16