Respostas

2013-11-27T14:11:46-02:00
A) 9x²-4 = 0

x² = 4/9
x=V4/9
x= +-2/3 

b) T²+7T=0
t(t+7)=0
t=0
t=7
duas raizes 0,7

c )3y²-5y=0
y(3y-5)=0
y=0 raizes 
3y-5=0
y=5/3

raizes 0 e 5/3