解方程:6x+4x=9x

解方程:6x+4x=9x
【正确答案】:(2/3)2+(4/9)x=1,(2/3)2x+(2/3)x-1=0,(2/3)2﹥0,则(2/3)x=[(√5)-1]/2,所以x=log2/3[(√5)-1]/2.