а) x(a-c)-ay+cy = x(a-c) - a(y-c) = x(a-c) - a(-1)(c-y)б) a(x-y)+by-bx = a(x-y) + b(y-x) = a(x-y)-b(x-y) = (a-b)(x-y)в) c(m+n)-dm-dn = c(m+n) - d(m+n) = (c-d)(m+n)
а) x(a-c)-ay+cy = x(a-c) - a(y-c) = x(a-c) - a(-1)(c-y)
б) a(x-y)+by-bx = a(x-y) + b(y-x) = a(x-y)-b(x-y) = (a-b)(x-y)
в) c(m+n)-dm-dn = c(m+n) - d(m+n) = (c-d)(m+n)