# A foot of the normal from the point $(4,3)$ to a circle is $(2,1)$ and a diameter of the circle has the equation $2x-y-2=0$.

A foot of the normal from the point $(4,3)$ to a circle is $(2,1)$ and a diameter of the circle has the equation $2x-y-2=0$.Then find the equation of the circle.

For the equation of the circle,we need to find the center and radius of the circle but from only the equation of the diameter,how should i find the center and the radius.Please suggest me some method.

• Hint: if you extend the normal vector between the two given points it will pass through the center of the circle. But the center must also lie on the diameter. – lulu Sep 20 '15 at 13:24
• @lulu,thank you,i got it. – learner_avid Sep 20 '15 at 13:43