       Re: vertices of a rectangle

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• Subject: [mg131275] Re: vertices of a rectangle
• From: W Craig Carter <ccarter at MIT.EDU>
• Date: Sun, 23 Jun 2013 22:55:38 -0400 (EDT)
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```Dear Clarice,
This sounds very much like a homework problem. Is it?

In case it is, here are some hints instead of a code answer:
Compute four vector for the sides. Take the dot products of the adjacent
sides. If all dot products are zero, then you have shown the vertices
are those of a rectangle.  For the area, you have two choices 1) if it
is a rectangle, then just multiply the lengths of two adjacent sides. 2)
If not, sum the magnitudes of the cross products for all triangles that
are part of the polygon.

If you are a student, then "it's" has a different meaning from "its".
If not, never mind.

WCC

On Jun 22, 13, at 20:46 PM, clarice wrote:

> need help for this :))
>
> show that the points A=(1,4), B=(7,0), C=(5,-3), D=(-1,1) are
the vertices of the rectangle, find it's area.
>

```

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