Question

Como eu resolvo essa equacao (x+5).(x-3)-x=5

Answer 1

x² - 3x + 5x - 15 - x - 5 = 0

x² + x - 20 = 0

Δ = 1 + 80
Δ = 81

x = - 1 +-√81/2
x = -1 +-9/2

x' = - 1 + 9/2
x'= 8/2 = 4

x'' = -1-9/2
x'' = -10/2 = -5           ok