#### Answer

(b) the product of the sum and difference of the same two terms

#### Work Step by Step

RECALL:
(1) $(a+b)^2$ is a square of a binomial
(2) $(a-b)(a+b)$ is the product of the sum and difference of the same two terms
The given expression can be written as:
$=(5a+6b)(5a-6b)$
The expression above is in the same form as the one in part (2) above.
Thus, the given expression is the product of the sum and difference of the same two terms.