以2X+3Y=0,2X-3Y=0为渐近线,则设方程是4x^2-9y^2=k.(k不=0)
坐标(1,2)代入得:4*1-9*4=k,k=-32
即方程是4x^2-9y^2=-32,即y^2/(32/9)-x^2/8=1