ANSWER
The correct answer is C.
[tex] |SU| = 8.1units[/tex]
EXPLANATION
The given points are,
[tex]S(2,1) \: \: and \: \: U(6,8).[/tex]
We use the distance formula to determine the distance between the two points.
[tex]d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2} [/tex]
We substitute the points to obtain,
[tex] |SU| = \sqrt{(6- 2) ^{2} + (8 - 1) ^{2} } [/tex]
We simplify to obtain,
[tex] |SU| = \sqrt{(4) ^{2} + (7) ^{2} } [/tex]
We further simplify this to obtain,
[tex] |SU| = \sqrt{16 + 49} [/tex]
[tex] |SU| = \sqrt{65} [/tex]
This evaluates to,
[tex] |SU| = 8.062[/tex]
We round to the nearest tenth to get,
[tex] |SU| = 8.1units[/tex]
