Respostas

2014-04-24T13:17:13-03:00
a) x² - 15 = 0
a = 1 ; b = 0 ; c = - 15

b) a = - 1 ; b = - 7 ; c = - 18

c) - 2y² + 15y = 0
a = - 2 ; b = 15 ; c = 0

d) a = 1 ; b = - 1 ; c = 3


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