a)(x + m)(y+n) =xy+xn + my+ mn;
б)(a-b)(x+ y) = ax + ay - bx– by
(x+m)(y+n)=xy+xn+my+mn=(xy+xn)+(my+mn)=x(y+n)+m(y+n)=(x+m)(y+n)
(a-b)(x+y)=ax+ay-bx-by=(ax+ay)-(bx-by)=a(x+y)-b(x+y)=(a-b)(x+y)
a)(x + m)(y+n) =xy+xn + my+ mn;
б)(a-b)(x+ y) = ax + ay - bx– by
(x+m)(y+n)=xy+xn+my+mn=(xy+xn)+(my+mn)=x(y+n)+m(y+n)=(x+m)(y+n)
(a-b)(x+y)=ax+ay-bx-by=(ax+ay)-(bx-by)=a(x+y)-b(x+y)=(a-b)(x+y)