jee-main 2011 Q68

jee-main · India Circles Circles Tangent to Each Other or to Axes

The two circles $x^{2}+y^{2}=ax$ and $x^{2}+y^{2}=c^{2}$ $(c>0)$ touch each other if
(1) $|a|=c$
(2) $a=2c$
(3) $|a|=2c$
(4) $2|a|=c$

The two circles $x^{2}+y^{2}=ax$ and $x^{2}+y^{2}=c^{2}$ $(c>0)$ touch each other if\\
(1) $|a|=c$\\
(2) $a=2c$\\
(3) $|a|=2c$\\
(4) $2|a|=c$