Ответ:\(3x^2-6x^3=3x^2(1-2x)\);\(15a^3+5a^2=5a^2(3a+1)\);\(9m^4-6m^3=3m^3(3m-2)\);\(7y^5+21y^3=7y^3(y^2+3)\);\(6z^4-12z^6=6z^4(1-2z^2)\);\(10a^6+30a^5=10a^5(a+3)\).