Respostas

2014-07-11T14:06:15-03:00
X (x+4)+3 (x+4)
x2+4x+3x+12
x2+7x+12
2014-07-11T14:10:52-03:00
(x + 3) × (x + 4)
x² + 4x + 3x + 12
x² + 7x + 12 = 0

BASKARA:
a = 1
b = 7
c = 12
 \frac{-b +-  \sqrt{b.b -4ac} }{2a}
 \frac{-7 +-   \sqrt{49 - 48} }{2}
 \frac{-7+-1}{2}

x'' \frac{-7+1}{2}
x'' = -3

x' =  \frac{-7-1}{2}
x' = -4
1 3 1