triangle DEF is formed by connecting the midpoints of the sides triabgle ABC. The lengths of the sides of DEF are shown. what is the length of AB​

Answer:6Step-by-step explanation:We know the theorem that if we connect the midpoints of any two sides of a triangle then the line so formed will be parallel to the third side and its length will be half of the length of the third side. Now, Δ DEF is formed by connecting the midpoints of sides of Δ ABC. Since line segment EF is formed by connecting the midpoint of side BC i.e. E and the midpoint of side AC i.e. F. Therefore, AC = 2 × EF = 2 × 3 = 6 (Answer)