Question

In triangle ABC,DandE are mid-point of AB and AC, respectively. Then,if DE =50CM, the length of BC is

Answer 1

according to the mid point theorem,
DE=1/2 BC
50=1/2 BC
2×50=BC
100cm= BC

hope it helps you

Answer 2

by mid point theorem
( in a triangle if a line connects two midpoints of two sides of the triangle then that line is parallel to the third side and is equal to half of it)
the length of the one joining two midpoints of the triangle ABC is DE = 50cm

DE= 1/2 BC
BC= 100cm