1. **State the problem:** Find the product of the binomials $$(7z + 4)(7z - 4)$$. 2. **Formula used:** This is a difference of squares pattern, where $$(a + b)(a - b) = a^2 - b^2$$. 3. **Identify terms:** Here, $a = 7z$ and $b = 4$. 4. **Apply the formula:** $$ (7z + 4)(7z - 4) = (7z)^2 - 4^2 $$ 5. **Calculate squares:** $$ (7z)^2 = 49z^2 $$ $$ 4^2 = 16 $$ 6. **Write the final expression:** $$ 49z^2 - 16 $$ 7. **Explanation:** The product of these two binomials is a difference of squares, which simplifies the multiplication process by squaring each term and subtracting. **Final answer:** $$49z^2 - 16$$