[tex]delta= b^{2} -4ac[/text]
[tex]x1= \frac{-b+ \sqrt{delta} }{2a} [/tex]
[tex]x2= \frac{-b- \sqrt{delta} }{2a} [/tex]
ex: [tex] 2x^{2} +5x+2=0
[/tex]
a=2
b=5
c=2
delta=25-16=9
[tex]x1= \frac{-5+ \sqrt{9} }{2*2} = \frac{-5+3}{4} = \frac{-2}{4} = \frac{-1}{2} [/tex]
[tex]x2= \frac{-5-3}{4} = \frac{-8}{4} =-2[/tex]