Jawabanmu

2014-09-13T16:53:24+07:00
2x . 2x + 2x . 3 + -3 . 2x + -3 . 3 =
4x^2  - 9
2014-09-13T16:59:58+07:00
(2x - 3) (2x + 3)
=4x² + 6x - 6x - 9
=4x² - 9