A rectangular swimming pool is to be built with an area of $4050$ square feet. The owner wants $5-$foot wide decks along either side and $10-$foot wide decks at the two ends. In this problem you will find the dimensions of the smallest piece of property on which the pool can be built satisfying these conditions.

If the dimensions of the swimming pool are denoted by x and y$,$ which of the following functions could be used to represent the area of the piece of property needed?

A$($x$)=$

$4050$x

$+10$

$($x $+20)$

A$($x$)=$

$4050$x

$5$

$($x $10)$

A$($x$)=$

$4050$x

$+10$

$4050$x

$+20$

A$($x$)=$

$4050$x

$10$

$($x $20)$

A$($x$)=$

$4050$x

$+5$

$($x $+10)$