1)-12aˇ2+18aˇ3=6aˇ2(3a-2)
2)2a+4b-ab-2bˇ2=2(a+2b)-b(a+2b)=(a+2b)(2-b)
3)xˇ2-64yˇ2=xˇ2-(8y)ˇ2=(x+8y)(x-8y)
4)-2xˇ3-28x2-98x=-2x(xˇ2+14x+49)=-2x(x+7)ˇ2
5)(x-4)ˇ2-25=(x-4)ˇ2-5ˇ2=(x-4+5)(x-4-5)=(x+1)(x-9)
6)aˇ6-8bˇ3=(aˇ2)ˇ3-(2b)ˇ3=(aˇ2-2b)(aˇ4+2aˇ2b+4bˇ2)