P=(1,0);Q(−1,0) Let A=(x,y)AQAP=BQBP=CQCP=31⇒3AP=AQ⇒9AP2=AQ2⇒9(x−1)2+9y2=(x+1)2+y2⇒9x2−18x+9+9y2=x2+2x+1+y2⇒8x2−20x+8y2+8=0⇒x2+y2−25x+1=0 ∴ A lies on the circle Similarly B, C are also lies on the same circle ∴ Circumcentre of ABC= Centre of Circle (1)=(45,0)