(x-a) (x + y)=х²+ху-ах-ау
(t + s)(b + k)=tb+tk+sb+sk
(a + 2) (6-3)=3(a+2)=3a+6
(d - 4) (t + 5)=dt+5d-4t-20
(a + 2)(n - m)=an-am+2n-2m
(c - d) (x - y)=cx-cy-dx+dy
(4-6) (5 + c)=-2(5+c)=10+2c
(k-6) (7-d)=7k-dk-42+6d
(x-a) (x + y)=х²+ху-ах-ау
(t + s)(b + k)=tb+tk+sb+sk
(a + 2) (6-3)=3(a+2)=3a+6
(d - 4) (t + 5)=dt+5d-4t-20
(a + 2)(n - m)=an-am+2n-2m
(c - d) (x - y)=cx-cy-dx+dy
(4-6) (5 + c)=-2(5+c)=10+2c
(k-6) (7-d)=7k-dk-42+6d