Question

$3x {}^{2} - 7x - 6 = 0$

Answer 1

Usando a fórmula de Bháskara:

$\Delta = b^2 - 4ac \\\Delta = (-7)^2 - 4 \cdot 3 \cdot (-6) \\\Delta = 49 + 72 \\\Delta = 121$

Para achar x:

$x=\dfrac{-b \pm \sqrt{\Delta}}{2a} = \dfrac{-7 \pm 11}{-6}= \boxed{3 \ \ ou \ -\dfrac{2}{3}}$