<PRE><B>Question 564726</B>
let the side of the square cardboard be x

4 in corners are to be cut

the dimensions of base will be (x-8) 

Volume of Box = L*W*H

100=(x-8)(x-8)*4

/4
25=(x-8)^2
25=x^2-16x+64
x^2-16x+39=0

x^2-13x-3x+39=0
x(x-13)-3(x-13)=0
(x-13(x-3)=0

x=13 OR 3

3 is not possible
so 13 in is the length of side of carboard

m.ananth@hotmail.ca</PRE>