$a^2{x}^2+2xy+9y^2=0representapairofdistinctlinesthen\text{'}a\text{'}lie\mathrm{s}in$

$\begin{array}{l}GivenEquation{a}^2{x}^2+2xy+9y^2=0\\ Comparingwitha{x}^2+2hxy+b{y}^2=0\\ a=a^2,h=1,b=9\\ GivenEquation\mathrm{Re}presentpairofdistinctlinesiff\\ h^2>ab\\ \Rightarrow 1>a^2\left(9\right)\\ \Rightarrow 9a^2-1<0\\ \Rightarrow \left(3a+1\right)\left(3a-1\right)<0\\ \therefore a\in \left(-\frac{1}{3},\frac{1}{3}\right)\end{array}$