Resposta :
Vamos là.
x² - 7x - 8 = 0
a = 1, b = -7, c = -8
delta
d = 49 + 32 = 81
as raízes
x1 = (7 + 9)/2 = 16/2 = 8
x2 = (7 - 9)/2 = -2/2 = -1
Vamos là.
x² - 7x - 8 = 0
a = 1, b = -7, c = -8
delta
d = 49 + 32 = 81
as raízes
x1 = (7 + 9)/2 = 16/2 = 8
x2 = (7 - 9)/2 = -2/2 = -1