Answer:
12(x-1) (x-6)
Explanation:
15(x - 4)(x -1)-3(x + 4)(x - 1)
We can factor out a 3 from both terms
3 ( 5(x - 4)(x -1)-(x + 4)(x - 1))
We can also factor out (x-1)
3(x-1) [5(x - 4)-(x + 4)]
Distribute inside the brackets
3(x-1) [5x-20 -x-4]
Combine like terms
3(x-1)[4x-24]
We can factor out a 4
3(x-1) 4[x-6]
12(x-1) (x-6)