F2Maths.......

ab(3x-1)-bc(3x-1)
=(ab-bc)(3x-1)
=b(a-c)(3x-1)

9mx-96ny+144my-6nx
=96ny-6nx+9mx+144my
=6n(16y-x)+9m(x+16y)
=6n(16y-x)-9m(16y-x)
=(6n-9m)(16y-x)
=3(2n-3m)(16y-x)

ab(3x-1)-bc(3x-1)
=(3x-1)(ab-bc)

9mx-96ny+144my-6nx
=9mx+144my-96ny-6nx
=9m(x+16y)-6n(16y-x)
=9m(x+16y)+6n(16y+x)
=(x+16y)(9m+6n)

I hope it can help you!

A
1)ab(3x-1)-bc(3x-1)
2)(ab-bc)(3x-1)
3)b(a-c)(3x-1)

B
1)9mx-96ny+144my-6nx
2)3(3mx-32ny+48my-2nx)
3)3(3mx-2nx+48my-32ny)
4)3[x(3m-2n)+16y(3m-2n)]
5)3[(x+16y)(3m-2n)]

ab(3x-1)-bc(3x-1)
=3abx-ab-3bcx+bc
=b(3ax-a-3cx+c)
=b[a(3x-1)-c(3x-1)]
=b(3x-1)(a-c)

9mx-96ny+144my-6nx
=9mx-6nx+144my-96ny
=3x(3m-2n)+48y(3m-2n)
=(3m-2n)(3x+48y)
=3(3m-2n)(x+16y)

ab(3x-1)-bc(3x-1)
=(3x-1)(ab-bc)//

9mx-96ny+144my-6nx
=9mx+144my-6nx-96ny
=9m(x+16y)-6n(x-16y)
=(x-16y)(9m-6n)
=3(x-16y)(3m-2n)//

ab(3x-1)-bc(3x-1)

=(ab-bc)(3x-1)..

(ab-bc)(3x-1)..就係答案~