Respostas

2013-08-30T16:38:14-03:00
[3x+2]/3= \/81-9'
=> 3x+2= 3*\/72'
=> 3x= 3*\/36*2' -2
=> 3x= 3*6\/2' -2
=> x= [18\/2' -2]/3
=> x= 6\/2' -2/3

Espero que tenha entendido. ^^
1 5 1
2013-08-31T00:11:33-03:00
Pelo que eu entendi é assim:
\frac{3x+2}{3}=\sqrt{81-9}\\\frac{3x+2}{3}=\sqrt{72}\\3x+2=3\sqrt{72}\\3x=3\sqrt{72}-2\\x=\frac{3\sqrt{72}-2}{3}\\x=\sqrt{72}-2