Ans : Mid Point Theorem: The Line segment in a triangle joining the mid point of two sides of the triangle is said to be parallel to its third side and is also half of the length of the third Side .
Consider the triangle ,ABC
Let E and D be the mid point of the side AC and AB.
Then the line DE is said to be Parallel to the side BC ,
⇒ DE || BC
⇒ DE = 1/2( BC)