x² +5x -10 = 0
x² +5x = 10
x² +5x + [tex] \frac{25}{4} [/tex] = 10 - [tex] \frac{25}{4} [/tex]
[tex](x+ \frac{5}{2})^{2} = \frac{65}{4}
[/tex]
x+ 5/2 = ± [tex] \sqrt{65}/4[/tex]
x = ± [tex] \sqrt{65}/4[/tex] -5/2
x = [tex] \frac{ \sqrt{65} -10 }{4} [/tex] ; x = [tex] \frac{- \sqrt{65} -10 }{4} [/tex]
