The answer is

Explanation: use Square of Sum
and use Difference of Squares
.
factor out the common term 6k
use Square of Sum then Difference of Squares
cancel k-6 then use the rule a/b*c/d=ac/bd

Hope this helps, now you know the answer and how to do it. HAVE A BLESSED AND WONDERFUL DAY! As well as a great rest of Black History Month! :-)
- Cutiepatutie ☺❀❤