х^2+15yz+3xz+5xy=x^2+3xz+5xy+15yz=x(x+3z)+5y(x+3z)=(x+3z)(x+5y)
х^2+15yz+3xz+5xy = x^2+3xz+5xy+15yz = x(x+3z)+5y(x+3z) = (x+5y)*(x+3z)
х^2+15yz+3xz+5xy=x^2+3xz+5xy+15yz=x(x+3z)+5y(x+3z)=(x+3z)(x+5y)
х^2+15yz+3xz+5xy = x^2+3xz+5xy+15yz = x(x+3z)+5y(x+3z) = (x+5y)*(x+3z)