Quadratic formula is:
[tex]x = \frac{- b +/- \sqrt{ b^{2} - 4ac} }{2a}[/tex]
Plug in:
[tex]x = \frac{-9 +/- \sqrt{9^{2} - 4(10)(-1)} }{2(10)} [/tex]
[tex]x = \frac{-9 +/- \sqrt{81 + 40}}{20} [/tex]
[tex]x = \frac{- 9 +/- \sqrt{121}}{20} [/tex]
[tex]x = \frac{- 9 +/- 11}{20} [/tex]
[tex]x = \frac{-9 - 11}{20} [/tex] and [tex]x = \frac{- 9 + 11}{20} [/tex]
[tex]x = \frac{- 20}{20} [/tex] and [tex]x = \frac{2}{20} [/tex]
[tex]x = - 1, \frac{1}{10} [/tex]
