Question

2 x ao quadrado menos 7x igual a 0

??? Preciso do da fórmula

Answer 1

$\large\boxed{\begin{array}{l}\sf 2x^2-7x=0\\\begin{cases}\sf a=2\\\sf b=-7\\\sf c=0\end{cases}\\\sf \Delta=b^2-4ac\\\sf\Delta=(-7)^2-4\cdot2\cdot0\\\sf\Delta=49\\\sf x=\dfrac{-b\pm\sqrt{\Delta}}{2a}\\\\\sf x=\dfrac{-(-7)\pm\sqrt{49}}{2\cdot2}\\\\\sf x=\dfrac{7\pm7}{4}\begin{cases}\sf x_1=\dfrac{7+7}{4}=\dfrac{14\div2}{4\div2}=\dfrac{7}{2}\\\\\sf x_2=\dfrac{7-7}{4}=\dfrac{0}{4}=0\end{cases}\\\\\sf S=\bigg\{0,\dfrac{7}{2}\bigg\}\end{array}}$