4(a-4)(a+1)
1) Factorizing 4a²-12a -16
4a²-12a -16 Note that the GCD (4,12,16) is 4, Rewrite them
4a²- 4*3a - 4* 4
2) 4(a² -3a -4) Rewrite a² -3a -4 answering the question, What are the numbers whose sum is 3 and product is 4?
Answer:
1 -4 = -3
1 x -4 = -4
3) Hence, the answer is:
4a²-12a -16= 4(a-4)(a+1)
