1) a*(b - c) + y*(b - c) = (a + y) * (b - c);
2) 3*(x + y) - b*(x + y)=(3 - b) * (x + y);
3) n * (4 - c) - (4 - c)= (n - 1) * (4 - c);
4) x^3 * (x^4 - 1) + 4 * (x^4 - 1) = (x^3 + 4) * (x^4 - 1);
5) 3m * (2n - 1) + (2n - 1) = (2n - 1) * (3m + 1);
6) 4а * (а^4 - 2) - 5у * (а^4 - 2) = (4а - 5у) * (а^4 - 2);
7) х * (а - b^2) - у * (а - b^2) - z * (a - b^2) = (x - y - z) * (a - b^2)