1/ (5x-4)² -49x² 2/ (2x+5)² -(x-9)² 3/ x²-2xy+y²-4m²+4mn-n² 4/ 2xy+3z+6y+xz 5/ 5x²+5xy-x-y 6/ x²-xy+x+y 7/ 2x²-2xy-7x-7y 8/ x²-3x+xy-3y 9/ x²+2x+1-16y²

Các câu hỏi liên quan