1. Simplify (a+b)² - (a+b)(a-b).
2. Find the complete factorization of 3x rise to 4 - 48.
3. Find the product of (4a-5b)(16a² + 20ab + 25b²)
4. What value of "c" makes 25x²-30xy+c a perfect square trinomial?
5. The area of a square is (25a²x²-30axy+9y²) square units. How long is its side?