x = 7 (option C)
Step-by-step explanation:
The triangle is an isosceles triangle. This means two angles and sides are equal.
The given sides are equal to each other. This because the the sides are opposite the angles equal to one another.
Equating the two legs or sides:
3x - 8 = 2x - 1
collect like terms:
3x - 2x = -1 + 8
x = 7 (option C)