Question

como se faz a eguação
$x { }^{2} = x + 12$
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Answer 1

Resposta:

$x^{2}=x+12\\x^{2}-x-12=0\\\\Aplicando~a~f\'{o}rmula~de~Bhaskara~para~x^{2}-x-12=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=1{;}~b=-1~e~c=-12\\\\\Delta=(b)^{2}-4(a)(c)=(-1)^{2}-4(1)(-12)=1-(-48)=49\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(-1)-\sqrt{49}}{2(1)}=\frac{1-7}{2}=\frac{-6}{2}=-3\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(-1)+\sqrt{49}}{2(1)}=\frac{1+7}{2}=\frac{8}{2}=4\\\\S=\{-3,~4\}$