Jawabanmu

2014-01-08T15:29:31+07:00
(3a-5)(3a+5)
=9a²+15a-15a-25
=9a²-25

semoga dapat membantu :)
2014-01-08T15:44:25+07:00
(3a-5) (3a+5) = 9a kuadrat +15a-15a-25
                    = 9a kuadrat - 25