Let me give you hints
The well known relationship is
d=r\theta
You know d and r, so you can find \theta
Now let us assume the circle is centered at origin and given point is on +ve x axis (r,0).
So x1=r y1=0;
Now x2= r cos\theta
and y2=r sin\theta
Also in this case x3=x2 and y3=-y2
From...
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