1) (a + b)(x - y); 4) (a + b)(a + 2);
2) (a - b)(x + y); 5) (y + 2)(y - 3);
3) (m-n)(p+q); 6) (a + 1)(a − 3);
7) (p + x) (q - y);
8) (a + b)(c-d);
9) (x + 1)(x - 1).
решить.​

ответ:

ax-ay+bx-by

ax+ay-bx-by

mp+mq-np-nq

pq-py+xq-xy

ac-ad-bc-bd

a²+2a+ba+2b

y²-3y+a-3

x²-x+x-1=x²-1

ответ 1(а+b)(x-y)=ax-ay+bx-by

2)(a-b)(x+y)=ax+ay-bx+by

3)(m-n)(p+q)=mp+mq-np-nq

4)(a+b)(a+2)=a²+2a+ba+2b

5)(y+2)(y-3)=y²-3y+2y-6

6)(a+1)(a-3)=a²-3a+a-3

7) (p + x) (q - y)=pq-py+xq-xy

8) (a + b)(c-d)=ac-ad+bc-bd

9) (x + 1)(x - 1)=x²-x+x-1