Question

x² + x - 12= 0
urgenteee!!​

Answer 1

x² + x - 12 = 0

A= 1

B= 1

C= - 12

∆= b² - 4ac

∆= 1² - 4 • 1 • ( - 12)

∆= 1 + 48

∆= 49

x= - b ± √∆/2a

x= - 1 ± √49 / 2 • 1

x= - 1 + 7 / 2

x'= - 1 + 7 / 2 = 6/2 = 3

x''= - 1 - 7 / 2 = - 8/2 = - 4

S= ( - 4 , 3)

Answer 2

Resposta:

$S = \{ - 4; \: 3 \}$

Explicação passo-a-passo:

${x}^{2} + x - 12 = 0$

$a = 1 \\ b = 1 \\ c = ( - 12)$

$\Delta = {b}^{2} - 4ac \\ \Delta = {1}^{2} - 4 \cdot1 \cdot( - 12) \\ \Delta = 1 + 48 \\\Delta = 49$

$x = \frac{ - b\pm \sqrt{\Delta} }{2a} \\ \\ x = \frac{ - 1\pm \sqrt{49} }{2\cdot1} \\ \\ x = \frac{ - 1\pm7}{2}$

$x_{1} = \frac{ - 1 + 7}{2} = \frac{6}{2} = 3 \\ \\ x_{2} = \frac{ - 1 - 7}{2} - \frac{8}{2} = - 4$

Olá Luciana, espero ter ajudado! :)