Question

-x2+9X-20=0 RESPONDER PARA MIM AS RAIZES.

Answer 1

Olá

$\boxed{\mathtt{-x^{2} + 9x - 20 = 0}}$

Multiplique toda a equação por um fator (-1)

$\boxed{\mathtt{[-x^{2} + 9x - 20 = 0]\cdot(-1)}}$

$\mathtt{x^{2} - 9x + 20 = 0}$

Use a fórmula de bháskara, sabendo que $\boxed{\mathtt{\Delta=b^{2} - 4ac}}}$

$\boxed{\mathtt{x=\dfrac{-b\pm\sqrt{\Delta}}{2a}}}$

Substitua os valores

$\mathtt{x=\dfrac{-(-9)\pm\sqrt{(-9)^{2}-4\cdot(1)\cdot(20)}}{2\cdot(1)}}$

Simplifique os valores

$\mathtt{x=\dfrac{9\pm\sqrt{81-80}}{2}}$

$\mathtt{x=\dfrac{9\pm\sqrt{1}}{2}}$

$\mathtt{x=\dfrac{9\pm1}{2}}$

Retire as raízes

$\boxed{\mathtt{x'=\dfrac{9+1}{2}~~\ \textgreater \ \ \textgreater \ ~~\dfrac{10}{2}~~\ \textgreater \ \ \textgreater \ ~~5}}}$

$\boxed{\mathtt{x"=\dfrac{9-1}{2}~~\ \textgreater \ \ \textgreater \ ~~\dfrac{8}{2}~~\ \textgreater \ \ \textgreater \ ~~4}}}$