Answer:
Step-by-step explanation:
[tex](2,4)=(x_1,y_1)\\(5,1,)=(x_2,y_2)\\\\d=\sqrt{\left(x_2-x_1\right)^2+\left(y_2-y_1\right)^2}\\\\d==\sqrt{\left(5-2\right)^2+\left(1-4\right)^2}\\\\d=\sqrt{3^2+3^2}\\\\d=\sqrt{3^2\times\:2}\\\\d=\sqrt{2}\sqrt{3^2}\\\\\mathrm{Apply\:radical\:rule\:}\sqrt[n]{a^n}=a,\:\quad \mathrm{\:assuming\:}a\ge 0\\\\\sqrt{3^2}=3\\d =3\sqrt{2}\\[/tex]