Answer:
4x² + 9y² + 12x - 18y - 12xy + 9
Explanation:
Given
(2x - 3y + 3)² = (2x - 3y + 3)(2x - 3y + 3)
Each term in the second factor is multiplied by each term in the first factor, that is
2x(2x - 3y + 3) - 3y(2x - 3y + 3) + 3(2x - 3y + 3)
Distribute the 3 parenthesis
= 4x² - 6xy + 6x - 6xy + 9y² - 9y + 6x - 9y + 9 ← collect like terms
= 4x² + 9y² + 12x - 18y - 12xy + 9