Question

Sendo x=\frac{-b+\sqrt{b^{2}-4.a.c}}{2.a}, calcule o valor de x para a = 3, b = -7 e c = 2.

Answer 1

$x = \frac{-b +/- \sqrt{b^{2}-4.a.c } }{2.a}$

$x = \frac{- (-7) +/- \sqrt{(-7)^{2}-4.3.2 } }{2.3} \\\\x = \frac{7 +/- \sqrt{49-24} }{6} \\\\x = \frac{7 +/-\sqrt{25} }{6} \\\\x' = \frac{7+5}{6} = \frac{12}{6} =2\\\\x'' =\frac{7 - 5}{6} = \frac{2:2}{6:2} = \frac{1}{3}$