Answers

2015-07-14T21:32:57+08:00
-b ±√b²−4ac
---------------
2a
0
X=-b ±√b²−4ac
------------------------
2a
X=-b ±√b²−4ac
------------------
2015-07-17T12:30:22+08:00
-b±√b²-4ac
x= ---------------
2a
0