<PRE><B>Question 313514</B>
the base is 4 feet by 5 feet.
the diagonal of the base has to be worked out.
using pythagoras theorem 
4^2+5^2= diagonal ^
25+16=diagonal^2
sqrt39 = diagonal
..
the base diagonal, The distance from the bottom left front corner to the top right back corner, and the height form a right triangle.

sqrt((sqrt39)^2+8^2))= the required length
sqrt(39+64)
= sqrt (103) 
=10.15 feet both will be same</PRE>