4xsquared-3xy+9ysquared-3 (5xy+7ysquared)
4x² - 3xy + 9y² - 3(5xy + 7y²)4x² - 3xy + 9y² - 3(5xy) - 3(7y²)4x² - 3xy + 9y² - 15xy - 21y²4x² - 3xy - 15xy + 9y² - 21y²4x² - 18xy - 12y²