Question

resolva essa EQUAÇÃO x^2+3x-80=0

Answer 1

Δ = b2 - 4.a.c 
Δ = 32 - 4 . 1 . -80 
Δ = 9 - 4. 1 . -80 
Δ = 329

Há 2 raízes reais.

$x = (\frac{-b +- \sqrt{329}}{2.a})$

$x' = \frac{15,13}{2}$

$x' = 7,56$

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$x'' = (\frac{-3 - \sqrt{329}}{2.1})$

$x'' = \frac{21,13}{2}$

$x'' = -10,56$