Respuesta :

Answer:

AB =12

Step-by-step explanation:

Since the base angles are the same, the sides are the same length

4x = 2x+6

subtract 2x from each side

4x-2x = 2x+6-2x

2x = 6

Divide by 2

2x/2 =6/2

x =3

AB =4x

     =4(3)

AB =12