
$\begin{aligned}
& \mathrm{L}_1 \equiv \frac{\mathrm{x}-2}{1}=\frac{\mathrm{y}-4}{5}=\frac{\mathrm{z}-2}{1}=\lambda \
& \mathrm{P}(\lambda+2,5 \lambda+4, \lambda+2) \
& \mathrm{L}_2 \equiv \frac{\mathrm{x}-3}{2}=\frac{\mathrm{y}-2}{3}=\frac{\mathrm{z}-3}{2} \
& \mathrm{P}(2 \mu+3,3 \mu+2,2 \mu+3) \
& \lambda+2=2 \mu+3 \quad 3 \mu+2=5 \lambda+4 \
& \lambda=2 \mu+1 \quad 3 \mu=5 \lambda+2 \
& 3 \mu=5(2 \mu+1)+2 \
& 3 \mu=10 \mu+7 \quad \
& \mu=-1 \quad \lambda=-1
\end{aligned}$
Both satisfies (P) $\begin{aligned}
& \mathrm{P}(1,-1,1) \
& \mathrm{L}_3 \equiv \frac{\mathrm{x}}{1 / 4}=\frac{\mathrm{y}}{1 / 2}=\frac{\mathrm{z}}{1} \
& \mathrm{~L}_3=\frac{\mathrm{x}}{\mathrm{l}}=\frac{\mathrm{y}}{2}=\frac{\mathrm{z}}{4}=\mathrm{k}
\end{aligned}$
Coordinates of Q(k,2k,4k) DR 's PQ=⟨k−1,2k+1,4k−1> PQ⊥ to L3 $\begin{aligned}
& (\mathrm{k}-1)+2(2 \mathrm{k}+1)+4(4 \mathrm{k}-1)=0 \
& \mathrm{k}-1+4 \mathrm{k}+2+16 \mathrm{k}-4=0 \
& \mathrm{k}=\frac{1}{7} \
& \mathrm{Q}\left(\frac{1}{7}, \frac{2}{7}, \frac{4}{7}\right) \
& \mathrm{PQ}=\sqrt{\left(1-\frac{1}{7}\right)^2+\left(-1-\frac{2}{7}\right)^2+\left(1-\frac{4}{7}\right)^2} \
& =\sqrt{\frac{36}{49}+\frac{81}{49}+\frac{9}{49}}=\frac{\sqrt{126}}{7} \
& P Q=\frac{3 \sqrt{14}}{7}
\end{aligned}$