Respuesta :

Answer:

BC = 34

Step-by-step explanation:

Given that ∠B = ∠C then the triangle is isosceles.

Thus AB and AC are congruent, that is

4x - 8 = 2x + 12 ( subtract 2x from both sides )

2x - 8 = 12 ( add 8 to both sides )

2x = 20 ( divide both sides by 2 )

x = 10

Hence

BC = 3x + 4 = (3 × 10) + 4 = 30 + 4 = 34