Theorem 8.10 : The line drawn through the mid-point of one side of a triangle, parallel to another side bisects the third side.

Explanation

In quadrilateral `EBCD`

`ED||BC` (given)

`EB||CD`

Since both pairs of opposite sides are parallel, `EBCD is parallelogram`

Since opposite sides of parallelogram are equal,

`EB=DC`

But, `E` is midpoint of `AB`,

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