Question

equação do segundo grau completa

Answer 1

Boa tarde Eloisa!

Solução!

$x^{2} +2x-3=0$


Formula de Bhaskara:

$x= \dfrac{-b\pm \sqrt{b^{2}-4.a.c } }{2.a} \\\\\\\\ x=\dfrac{-2\pm \sqrt{2^{2}-4.1.-3 } }{2.1} \\\\\\\\ x=\dfrac{-2\pm \sqrt{4+12 } }{2} \\\\\\\\ x=\dfrac{-2\pm \sqrt{16 } }{2} \\\\\\\\ x=\dfrac{-2\pm 4 }{2} \\\\\\\\ x_{1} = \dfrac{-2+4}{2}= \dfrac{2}{2}=1\\\\\\\ x_{2} = \dfrac{-2-4}{2}= \dfrac{-6}{2}=-3 ~~Nao~~serve$

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