Answer:
A. 10
Step-by-step explanation:
To find the distance between two points you use this equation.
[tex]\sqrt{(x2 - x1)^{2} + (y2 - y1)^{2} }[/tex]
Next we replace the values.
[tex]\sqrt{(8-2)^{2} + (-1 - 7)^{2} }[/tex]
Next we subtract the values.
[tex]\sqrt{6^{2} + (-8)^2}[/tex]
Next we square the values to get 36 and 64.
[tex]\sqrt{36 + 64}[/tex]
Finally we take the square root of of those two numbers added together.
[tex]\sqrt{100}[/tex] = 10