[tex]\sqrt{\dfrac{225}{69}}=\dfrac{\sqrt{225}}{\sqrt{69}}=\dfrac{15}{\sqrt{69}}=\dfrac{15\sqrt{69}}{\sqrt{69}\cdot\sqrt{69}}=\dfrac{15\sqrt{69}}{69}=\dfrac{5\sqrt{69}}{23}\\\\Used:\\\\\sqrt{a}\cdot\sqrt{a}=a[/tex]
