Question

The abscissae of A and B are the roots of the equation $x^2+2ax-b^2=0$ and their coordinates are the roots of the

equation y^2 + 2py - q^2 = 0. The equation of the circle with AB as diameter

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

Let $A(x_1,y_1)$ and $B(x_2,y_2)$, then

$x_1+x_2=-2a$, $x_1{x}_2=-b^2$

$y_1+y_2=-2p$, $y_1{y}_2=-q^2$

Now find centre and radius and hence the equation of circle.