Answer:
(3x - 1)(x + 1)
Explanation:
3x^2 factors into 3x and x.
-1 factors into -1 and 1.
Now we try different positions of 3x, x, -1, and 1 until we find the correct factorization.
Try: (3x - 1)(x + 1)
When you multiply the two factors together, the middle term will be 3x - x = 2x
Since 2x is the original middle term, this is the correct factorization.
Answer: (3x - 1)(x + 1)