Thread: Coordinate Geometry Proofs

Given:

A(–2,2), B(6,5), C(4,0), D(–4,–3)

Prove: ABCD is a parallelogram but not a rectangle.

Originally Posted by magentarita

Given:

A(–2,2), B(6,5), C(4,0), D(–4,–3)

Prove: ABCD is a parallelogram but not a rectangle.

ABCD is a parallelogram --->
1. lengths AB=CD
2. lengths AD=BC

Or in terms of vectors :


A sketch can make you understand why I chose these letters.

Originally Posted by Moo

ABCD is a parallelogram --->
1. lengths AB=CD
2. lengths AD=BC

Or in terms of vectors :


A sketch can make you understand why I chose these letters.

Thanks for the tip.