Thread: Vector Proof Problem

Please help with this vector proof!

'Let ABCD be a quadrilateral in the plane, and let P and Q be the midpoints of of the sides AB and CD respectively. Show that:

2PQ = AD + BC'

I'm just not sure how to go about it. Thanks in advance for any help.

Originally Posted by AlanC877

Let ABCD be a quadrilateral in the plane, and let P and Q be the midpoints of of the sides AB and CD respectively. Show that: 2PQ = AD + BC'

Now add those together.

Thanks very much, now I realise just how easy the question actually was!