#### Answer

$(8r^{3}-9)^{2}$

#### Work Step by Step

Given the polynomial
$(8r^{3})^{2}$ - 144x + $(9)^{2}$
We see that the polynomial has the first and last term squared and the middle term is -2 times the first and last term. Thus it follows the rule of
$a^{2}$ - 2ab + $b^{2}$ = $(a-b)^{2}$
In this polynomial a= $8r^{3}$ and b=9
$8r^{3}$ - 2($8r^{3}$)(9) + $(9)^{2}$ = $(8r^{3}-9)^{2}$