Ответ:\(a^2+a=a(a+1)\);\(x^3-x^2=x^2(x-1)\);\(c^5+c^7=c^5(1+c^2)\);\(a^3-a^7=a^3(1-a^4)\);\(3m^2+9m^3=3m^2(1+3m)\);\(9p^3-8p=p(9p^2-8)\);\(4c^2-12c^4=4c^2(1-3c^2)\);\(5x^5-15x^3=5x^3(x^2-3)\);\(-12y^4-16y=-4y(3y^3+4)\).