Question

x sobre 2 - 4x - 5=0​

Answer 1

x² -4x -5 = 0

∆=b²-4ac= 16+20=36 => √∆=6

x = -b±√∆/2a

x = 4±6/3

x' = 4+6/2 = 10/2 = 5 ✓

x" = 4-6/2 = -2/2 = -1✓