Answer:
Step-by-step explanation:
[tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\\\\(-5,6)\quad\implies\quad x_1=-5\,,\ y_1=6\\\\(8,4)\quad\implies\quad x_2=8\,,\ y_2=4\\\\\\d=\sqrt{(8+5)^2+(4-6)^2}= \sqrt{13^2+(-2)^2}=\sqrt{169+4}=\sqrt{173}\approx13.2[/tex]
