A box without a top is made from a rectangular piece of cardboard, with dimensions 9 m by 7 m, by cutting out square corners with side length x.

AWhat algebraic expression represents the length of the box? (In this problem, the length is the longer of the two dimensions.)

BWhat algebraic expression represents the width of the box?

CWhat algebraic expression represents the height of the box?

DWhat algebraic expression represents the volume of the box? Leave your expression in factored form.

EUsing technology, estimate the value of x that gives the greatest volume, to the nearest tenth.