Question

109. If the angle of intersection of the circles $x^2+y^2+x+y=0$ and $x^2+y^2+x-y=0$ is the equation of the line passing through $(1,2)$ and making an angle with the y-axis is

• A. $x=1$
• B. $y=2$
• C. $x+y=3$
• D. $x-y=3$

Answer 1

The correct option is B $y=2$

$x^2+y^2+x+y=0...\left(i\right)$
and $x^2+y^2+x-y=0...\left(ii\right)$
Subtracting (ii) from (i) we get
$2y=0$
$\Rightarrow y=0$
Hence x axis.
Hence the angle is $0^0$
Thus the required line is $y=2$