Polar of the point (x1,y1) with respect to the circle 5x2+5y2=9 is given by 5xx1+5yy1=9
Comparing the above equation with the equation of the straight line 2x−y=1, we have
5x12=5y1−1=91
⇒5x1=9×2=18
or x1=185
Also, 5y1=−9 or y1=−95
The pole is thus (185,−95)