Final answer:
The perimeter of the triangle with given side lengths 3X, (X-1), and 2(X+4) is 6X + 7.
Step-by-step explanation:
To find the perimeter of a triangle with side lengths of 3X, (X-1), and 2(X+4), we need to add up the lengths of all three sides. The perimeter is the sum of all the side lengths.
Perimeter = 3X + (X-1) + 2(X+4)
Simplifying the expression, we get Perimeter = 3X + X - 1 + 2X + 8 = 6X + 7.
Therefore, the correct answer is 6X + 7 (option B).