Answer is C. multiply by 3 - square root 5
using a^2 - b^2 = (a + b)(a - b)
Answer:

Step-by-step explanation:

My answer:
I’m pretty sure it’s A. Correct me if I’m wrong
3,868,000,000 is your answer. Move the decimal to the right 9 times. That gives you 6 extra 0’s.
The answer to your question is c