Question

-x²-2x+8=0 Gente me ajudem

Answer 1

- x²- 2x + 8 = 0

delta = b² - 4ac

delta = (-2)² - 4 . (-1) . (8)

delta = 4 + 32

delta = 36

x = ( - b +- raiz de delta ) / 2a

x = ( - (-2) +- raiz de 36 ) / 2.(-1)

x = ( 2 +- 6 ) / - 1

x' = ( 2 - 6 ) / - 1 = - 4 / - 1 = 4

x" = ( 2 + 6 ) / - 1 = 8 / - 1 = - 8