Factorization help?

Question

a^2+3b^2+4ab+2ac+6bc-4b+4c-4

Can you explain how to factorize it please?

Answer 1

a^2+3b^2+4ab+2ac+6bc-4b+4c-4
= a^2 + 4ab + 4b^2 - b^2 + 2ac+6bc-4b+4c-4
= (a + 2b)^2 +c( 2a + 4) + c( 6b -4) - (b -2)^2

Answer 2

3b(b + 2c) + a(a + 4b + 2c) -4(b - c + 1);

you may have more luck gathering other terms...

for example:
3b^2 - 4b -4 +a^2 + 4ab +2ac +6bc + 4c
(3b + 2)(b - 2) + a(a + 4b) + 2c(a + 3b + 2)