
Nguyễn Trần Thành Đạt 11/03/2017 at 00:06
\(\dfrac{1}{z}=\dfrac{z}{9}\\ < =>1.9=z.z\\ < =>z^2=9\\ =>z=3orz=3\)
Nguyễn Hải Nam selected this answer.
\(\dfrac{1}{z}=\dfrac{z}{9}\\ < =>1.9=z.z\\ < =>z^2=9\\ =>z=3orz=3\)
Nguyễn Hải Nam selected this answer.