Respostas

2014-08-14T11:52:18-03:00
X² - 23x + 120 = 0
x = b² - 4ac = 23² - 4.1.120 = 529 - 480 = 49
√Δ = √49 = 7
x' = (23+7) /2 = 30/2 = 15
x" = (23-7) /2 = 16/2  = 8