Respuesta :

Answer:

[tex]\boxed{\sf \ \ \ diagonal \ length \ = \ 41 \ \ \ }[/tex]

Step-by-step explanation:

Thanks to Pythagoras we can say that

l being the length of the diagonal

[tex]l =\sqrt{9^2+40^2}=\sqrt{81+1600}=\sqrt{1681}=41[/tex]