Posted by jimmy on Friday, June 29, 2012 at 8:25am.
subtract:
7z/z5  4z9/5z

algebra1  Reiny, Friday, June 29, 2012 at 10:30am
I am sure you meant:
(7z)/(z5)  (4z9)/(5z)
= (7z)/(z5) + (4z9)/(z5)
= (7z + 4z9)/(z5)
= (3z2)/(z5)