Respostas

2014-07-24T15:58:28-03:00
X-4 = 5/x
x²-4x=5
     x
x²-4x-5=0
Δ= 16+20
Δ=36
x=-(-4)+-√36
       2.1

x'= 4 + 6 = 10 = 5
        2        2

x"=  4 - 6 = -2 = -1
          2       2