Answer:
ITS B
Step-by-step explanation:
B
triangle ABC is an isosceles triangle since there are two equal angles
hence,
AB = BC
4x = 2x + 6
4x - 2x - 6 = 0
2x - 6 = 0
2x = 6
x = 3
AB = 4x
AB = 4 * 3
AB = 12