Respostas

2013-11-23T16:26:53-02:00
5 x^{2} = 49 - 4
5 x^{2} = 45
 x^{2} = 45/ 5
 x^{2} = 9
2013-11-23T16:27:22-02:00
5x²+4=49
5x²=49-4
5x²=45
x²=45/5
x²=9
x= \sqrt{9}
x= \pm 3
1 5 1