Respostas

2014-07-14T12:50:41-03:00
X²-8x-20=0

a=1
b=-8
c=-20

∆=b²-4.a.c
∆=(-8)²-4.1.(-20)
∆=64+80
∆=144

x'=-(-8)+√144/2.1=8+12/2=20/2=10
x''=-(-8)-√144/2.1=8-12/2=-4/2=-2
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