$\begin{aligned}
& \mathrm{x}(3 \lambda+1)+\mathrm{y}(7 \lambda+2)=17 \lambda+5 \
& (\mathrm{x}+2 \mathrm{y}-5)+\lambda(3 \mathrm{x}+7 \mathrm{y}-17)=0
\end{aligned}$
intersection of family of lines
P(1,2)
Let Q(3,6)
$\begin{aligned}
& \mathrm{d}=\mathrm{PQ}=\sqrt{2^2+4^2}=\sqrt{20} \
& \mathrm{~d}^2=20
\end{aligned}$
option (1)