Let P(a1,b1) and Q(a2,b2) be two distinct points on a circle with center C(2,3). Let O be the origin and OC be perpendicular to both CP and CQ. If the area of the triangle OCP is 235, then a21+a22+b21+b22 is equal to :
Answer: 24
Solutions · 1
Official solution
OC⊥CP and OC⊥CQ⇒PCQ is a straight line
OC=(2)2+(3)2=5
Let CP=CQ=I[OCP]=21×OC×I=235I=7OP=OQ=(OC)2+I2=5+7=12a21+a22+b21+b22=(a21+b22)+(a22+b22)OP2+OQ2=12+12=24