AP EAMCET Engineering 2013 Solved Paper

Given equations of circle is
x2+y2=16
and x2+y2+2x+2y=0
According to the questions,
Length of the tangent from (h,k) to the circle
x2+y2=16
=2× Length of the tangent from (h,k) to the circle x2+y2+2x+2y=0
⇒ √h2+k2−16=2 ×√h2+k2+2h+2k
On squaring both sides, we get
h2+k2−16=4×(h2+k2 +2h+2k)
⇒ 3h2+3k2+8h+8k+16=0