HELP FAST ASAP THIS IS DUE IN LESS THAN AN HOUR

Answer:
9x^2 -1
Step-by-step explanation:
(3x-1) (3x+1)
FOIL
first: 3x*3x = 9x^2
outer:3x*1 =3x
inner: -1 *3x = -3x
last: -1*1 = -1
Add them together
9x^2 +3x-3x-1
Combine like terms
9x^2 -1
Answer:
9x²-1
Step-by-step explanation:
1) (3x-1)(3x+1)
transfer difference of squares using this rule:
(a-b) (a+b) = a²-b²
2) (3x)²-1²
expand (3x)²
3) 3²x²-1²
calculate 3 to the power of 2 and 9
4) 9x²-1²
calculate 1 to the power of 2 and get 1
5) 9x²-1
you recieve your answer, B.