Answer :
Answer:
a^2 + 2ab + b^2 - c^2
Step-by-step explanation:
When you multiply all the terms together you get a^2 + ab + ac + ab + b^2 + bc - ac - bc - c^2. Then you can just combine like terms and simplify it to a^2 + 2ab + b^2 - c^2. Hope this helps :)