Question

-x ao quadrado + 6x -8 = 0​

Answer 1

-x² +6x -8 = 0

a = -1, b = 6 e c = -8

x = -b ±√∆/2a

x = -(6) ±√(6)² -4(-1)(-8)/2(-1)

x = -6 ±√36 -32/-2

x = -6 ±√4/-2

x = -6 ±2/-2

x' = -6 +2/-2

x' = 2

x" = -6 -2/-2

x" = 4