An open box is to be made from a flat piece of material 20 inches long and 6 inches wide by cutting equal squares of length $x$from the corners and folding up the sides.

Write the volume $V$of the box as a function of $x$. Leave it as a product of factors, do not multiply out the factors.

$V =$

If we write the domain of the box as an open interval in the form (a,b), then what is $a =$?

$a =$

and what is $b =$?

$b =$