Question

3b*3-24
a*2-8ay+16y*2+3a-12y

Answer 1

3b³-24=3(b³-8)=3(b-2)(b²+2b+4)
a²-8ay+16y²+3a-12y=(a-4y)²+3(a-4y)=(a-4y)(a-4y+3)