将圆方程化简为标准式有：
[x+(1/2)]^2+(y-3)^2=(37-4m)/4……………………………（1）
所以,圆心坐标为(-1/2,3)
联立直线与圆方程得到：
x^2+x+y^2-6y+m=0
x+2y-3=0
===> (2y-3)^2-(2y-3)+y^2-6y+m=0
===> 4y^2-12y+9-2y+3+y^2-6y+m=0
===> 5y^2-20y+(m+12)=0
===> y1+y2=4,y1y2=(m+12)/5
===> x1x2=(-2y1+3)(-2y2+3)=4y1y2-6(y1+y2)+9=4(m+12)/5-15
已知OP⊥OQ
则,Kop*Koq=-1
即：(y1/x1)*(y2/x2)=-1
===> y1y2+x1x2=0
===> (m+12)/5+4(m+12)/5-15=0
===> m+12-15=0
===> m=3