Question

2(3x+ 4)
(2x+3)(5x-2)

Answer 1

2(3x+ 4)

6x + 8 =

6x = - 8

$x = \frac{ - 8}{6} (simplificando \: por \: 2)$

$x = \frac{ - 4}{3}$

x = - 1, 33

(2x+3)(5x-2) =

10x² - 4x + 15x - 6 =

10x² + 11x - 6 = 0

DELTA = b² - 4 × a× c

DELTA = 11² - 4 × 10 × - 6

DELTA = 121 + 240

DELTA = 361

$x = \frac{ - b + - \sqrt{delta} }{2a}$

$x = \frac{ - 11 + - \sqrt{361} }{2 \times 10}$

$x = \frac{ - 11 + - 19}{20}$

$x1 = \frac{ - 11 - 19}{20}$

$x1 = \frac{ - 30}{20} (simplificando \: por \: 10)$

x1 = - 3 / 2

$x1= - 1.5$

$x2 = \frac{ - 11 + 19}{20}$

$x2 = \frac{8}{20} (simplificando \: por \: 4)$

$x2 = \frac{2}{5}$

x2 = 0, 4

S = { - 1, 5 , 0, 4 }