Hello from MrBillDoesMath!
Answer:
10 - 3 sqrt(2)
Discussion:
Let f(x) = 6 + sqrt(14 + x) - sqrt(9x).
Then
f(2) = 6 + sqrt(14 + 2) - sqrt(9*2)
= 6 + sqrt(16) - sqrt(9*2) => sqrt(16) = 4
= 6 + 4 - sqrt(9)*sqrt(2) => sqrt(9) = 3
= 10 - 3 sqrt(2)
which is the first choice.
Thank you,
MrB
