What is ​ BC ​?Enter your answer in the box.

Answer-The length of BC is 8 units.Solution-Mid-Point Theorem-The line segment connecting the midpoints of  two sides of a triangle is parallel to the third side and is congruent to one half of the third side.As given,AD = DB, so D is the mid point of ABFA = FC, so F is the mid point of ACHence, DF is the line segment connecting the midpoints of  two sides of a triangle.Applying the theorem,BC = 2DF = 2×4 = 8 units