Q.

If P(6,1) be the orthocentre of the triangle whose vertices are A(5, -2), B(8, 3) and C(h, k), then the point C lies on the circle                    [2024]

1 x2+y2-65=0  
2 x2+y2-74=0  
3 x2+y2-52=0  
4 x2+y2-61=0  

Ans.

(1)

Slope of AP=1+26-5=3

Slope of BC=-1Slope of AD

=-1Slope of AP

=-13

Equation of line BC is given by (y-3)=-13(x-8)

3y+x-17=0                                        ...(i)

Now, slope of BP=1-36-8=1

Slope of AC=-1

Equation of AC is y+2=-1(x-5)

i.e., y+x-3=0                                           ...(ii)

C is the point of intersection of AC and BC, then solving equation (i) and (ii), we get

C=(-4,7), which lies on the circle x2+y2-65=0.