The segment was only rotated, not changed. It would be the same length as the original.
To find the length, use the distance formula.
[tex] \sqrt{ {(x2 - x1)}^{2} + ( {y2 - y1)}^{2} } [/tex]
(5, 8) would be point 1.
(-6,8) would be point 2.
Plug them into the formula.
[tex] \sqrt{( { - 6 - 5)}^{2} + ( {8 - 8)}^{2} } [/tex]
Simplify.
[tex] \sqrt{( { - 11)}^{2} + ( {0)}^{2} } [/tex]
[tex] \sqrt{121 + 0} [/tex]
[tex] \sqrt{121} [/tex]
Square root this answer.
[tex] \sqrt{121} = + or - 11[/tex]
Negative distances aren't possible, so your answer is 11.
Hope this helped!
:)