Respostas

2014-08-01T00:24:03-03:00
X^2 - 7x - 30 = 0

Delta = b^2 - 4.a.c

Delta = 49 - 4.1. (-30)

Delta = 49 + 120

Delta = 169

X = -b +/- raiz de delta / 2.a

X = 7 +/- 13 / 2

X ' = -6 / 2
X ' = -3

X " = 20 / 2
X " = 10