Respostas

2014-05-22T18:09:43-03:00
X² +2x -8= 0
a= 1  b=2  c= -8
Δ= b² -4.a.c
Δ=(2)² -4 . 1 . -8
Δ=4 + 32
Δ=36
x= \frac{-b+- \sqrt{Δ} }{2.a}
x= \frac{-(-8)+- \sqrt{36} }{2.1}
x'= \frac{8+6}{2}
x'= \frac{14}{2}
x'=7
x''= \frac{8-6}{2}
x''= \frac{2}{2}
x''=1
1 5 1
2014-05-22T18:13:57-03:00
A=1 b=2 c=-8
Δ= 2².-4.1.-8
       2.a
Δ=4.-4.1.-8
  2.1
Δ-16.-8= 128/2
Δ=64
ai vc tem q fazer o valor do x