Answer :
[tex]\sqrt{18}=\sqrt{9\cdot2}=\sqrt9\cdot\sqrt2=3\sqrt2\\\\\sqrt{18}\approx4.24\\\\\sqrt{50}=\sqrt{25\cdot2}=\sqrt{25}\cdot\sqrt2=5\sqrt2\\\\\sqrt{50}\approx7.07\\\\\sqrt{27x^3y}=\sqrt{9\cdot3x^2xy}=\sqrt{9x^2}\cdot\sqrt{3xy}=3x\sqrt{3xy}[/tex]
