Question

(precisa fazer a conta)

Answer 1

a) 2x² - 6x - 8 = 0

Utilize Bhaskara

$x = \frac{ - b± \sqrt{ {b}^{2} - 4ac} }{2a}$

a = 2

b = -6

c = -8

$x = \frac{6± \sqrt{36 - 4(2)( - 8)} }{4} \\ x = \frac{6± \sqrt{36 + 64} }{4} \\ x = \frac{6± \sqrt{100} }{4} \\ x = \frac{6±10}{4} \\ x1 = \frac{6 + 10}{4} = \frac{16}{4} = 4 \\ x2 = \frac{6 - 10}{4} = \frac{ - 4}{4} = - 1$

b) 5x² - 3x - 2 = 0

Utilizando Bhaskara

a = 5

b = -3

c = -2

$x = \frac{3± \sqrt{9 - 4(5)( - 2)} }{10} \\ x = \frac{3± \sqrt{9 + 40} }{10} = \frac{3± \sqrt{49} }{10} \\ x1 = \frac{3 + 7}{10} = \frac{10}{10} = 1 \\ x2 = \frac{3 - 7}{10} = \frac{ - 4}{10} = \frac{ - 2}{5}$