Respostas

2014-06-26T09:08:15-03:00
(x+2)(x-16)+(x+7)=89

x² - 16x + 2x - 32 + x + 7 - 89 = 0
x² - 13x - 114 = 0
169 + 456
delta = 625

13 +- 25 / 2
x' = 19
x" = -6

S={-6, 19}