Question

x elevado a 2+x-56=0

Answer 1

$\frac{-1\pm\sqrt{1^2-4\cdot1\cdot(-56)}}{2\cdot1}  =\frac{-1\pm\sqrt{1+224}}{2}  =\frac{-1\pm\sqrt{225}}{2}  =\frac{-1\pm15}{2}$

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