it The length of the diagonal can be gotten using the Pythagorean Theorem, given to be:
[tex]c^2=a^2+b^2[/tex]
where c is the hypotenuse/diagonal and a and b are the other two sides/length of the square.
We have that:
[tex]a=b=5[/tex]
Therefore, we can solve as follows:
[tex]\begin{gathered} c^2=5^2+5^2 \\ c^2=25+25 \\ c^2=50 \\ c=\sqrt{50} \\ c=5\sqrt{2} \end{gathered}[/tex]
OPTION D is the correct option.
