Question

Com a fórmula resolutiva, resolva as seguintes equações 2x2+7x+5=0

Answer 1

A) 2x² + 7x + 5 = 0 
Delta = b² - 4ac
Delta = 49 - 4(2)(5)
Delta = 49 - 40
Delta = 9

X = (-b +- raiz delta) / 2a
X = (-7 +- 3) / 4
x' = (-7 + 3) / 4 = -4/4 = -1
x" = (-7 - 3) / 4 = -10/4 = -5/2

Answer 2

$2x^2 \ + 7x \ + \ 5 \ = \ 0\\ \\ \Delta \ = \ b^2 \ - \ 4.a.c\\ \Delta \ =\ (7)^2 \ - \ 4.(2).(5)\\ \Delta \ = \ 49 \ - \ 40 \\ \Delta \ =\ 9 \\ \\ x = \frac{-b \ \pm \sqrt{\Delta}}{2a}\\ \\ x = \frac{-7 \ \pm \ {3}}{4}\\ \\ x' = \ -1\\ x'' \ = \ \frac{-5}{2}$