(x-3)*(x-3)/x*x=4/9
则9(x-3)²=4x²
则9(x-3)²-4x²=0
则【3(x-3)+2x】【3(x-3)-2x】=0
则(5x-9)(x-9)=0
则5x-9=0或x-9=0
解得x=9/5或x=9