初一数学题有图急求!要过程答案我有万分感谢

1个回答

原式
= (X-3)² - [X-(2Y-3)]*[X+(2Y-3)]
= (X-3)² - X² + (2Y-3)²
= -6X+9 + 4Y²-12Y+9
= -6X + 4Y² - 12Y + 18