Question

equação do segundo grau x2 - 10x + 9 = 0 fórmula de Bhaskara​

Answer 1

$\large \text{ \sf{S=\{9,1\}} }$

Explicação passo-a-passo:

$\large \text{ \sf{x {}^{2} - 10x + 9 = 0 } }$

$\large \text{ \sf{ \begin{cases} \sf{a = 1} \\ \sf{b = - 10} \\ \sf{c = 9}\end{cases}} }$

$\large \text{ \sf{\Delta = b {}^{2} -4 \cdot{a} \cdot{c} } }$

$\large \text{ \sf{\Delta = ( - 10) {}^{2} - 4 \cdot1 \cdot9 } }$

$\large \sf{\Delta = 100 - 36 }$

$\large \sf{\Delta = 64 }$

$\large \text{ \sf{x = \dfrac{ - b \pm \sqrt{ \Delta}}{2 \cdot{a}} } }$

$\large \text{ \sf{x = \dfrac{ - ( - 10) \pm \sqrt{64} }{2 \cdot{1}} } }$

$\large \text{ \sf{x = \dfrac{10 \pm8}{2} \begin{cases} \sf{x _{1} = \dfrac{10 + 8}{2} = \dfrac{18}{2} = 9 } \\ \\ \sf{x _{2} = \dfrac{10 - 8}{2} = \dfrac{ 2}{2} =1 }\end{cases}} }$