RSCx,y=Px/Py
PxQx+PyQy=m
则,RCSx,y=-dY/dX=20/Y=Px/Py=2/5
2Qx+5Qy=270
即Qx=10,Qy=50
RSCx,y=Px/Py
PxQx+PyQy=m 则,RCSx,y=-dY/dX=20/Y=Px/Py=2/5 2Qx+5Qy=270 即Qx=10,Qy=50