The polynomial identity for the difference of two squares states that \( a^2 - b^2 = (a - b)(a + b) \).
In your case, you want to express \( 81 - 16 \) using this identity.
First, we recognize that:
- \( 81 \) can be written as \( 9^2 \) (since \( 9 \times 9 = 81 \)),
- \( 16 \) can be written as \( 4^2 \) (since \( 4 \times 4 = 16 \)).
Now you can apply the difference of squares identity:
\[ 81 - 16 = 9^2 - 4^2 = (9 - 4)(9 + 4). \]
Calculating the expressions in parentheses, we get:
\[ (9 - 4)(9 + 4) = 5 \cdot 13. \]
Thus, the product equal to \( 81 - 16 \) is:
\[ (9 - 4)(9 + 4) = 5 \cdot 13. \]