1) 2а(х+ у) + х + у = 2ах + 2ау + х + у = (2ах + х) + (2ау + у) = х(2а + 1) + у(2а + 1) = (х+ у) · (2а + 1)
2) 5х(а + b) - a - b = 5ax + 5bx - a - b = (5ax - a) + (5bx - b) = a(5x - 1) + b(5x - 1) = (a +b) · (5x - 1)
3) 3m(x + y) - x - y = 3mx + 3my - x - y = (3mx - x) + (3my - y) = x(3m - 1) + y(3m - 1) = (x + y) · (3m - 1)
4) x(a - b) + a - b = ax - bx +a - b = (ax + a) - (bx + b) = a(x + 1) - b(x +1) = (a - b) · (x +1)
5) 4y(k - p) - k + p = 4ky - 4py - k + p = (4ky - k) - (4py - p) = k(4y - 1) - p(4y - 1) = (k - p) · (4y - 1)
6)2a(x - y) - x + y = 2ax - 2ay - x + y = (2ax - x) - (2ay - y) = x(2a - 1) - y(2a - 1) = (x - y) · (2a - 1)