http://img443.imageshack.us/img443/2...265485tkvf.png

One of the Quadrilateral is a parallelogram and one not.

Who isn't a parallelogram and why

thanks!

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- Dec 8th 2011, 07:29 AMmentaman10parallelogram - proof
http://img443.imageshack.us/img443/2...265485tkvf.png

One of the Quadrilateral is a parallelogram and one not.

Who isn't a parallelogram and why

thanks! - Dec 8th 2011, 08:01 AMPlatoRe: parallelogram - proof
- Dec 8th 2011, 08:07 AMmentaman10Re: parallelogram - proof
yes

- Dec 8th 2011, 08:17 AMPlatoRe: parallelogram - proof
- Dec 8th 2011, 08:26 AMmentaman10Re: parallelogram - proof
not rectangle, parallelogram.

and that doesn't give me nothing, the teacher gave me to do that..

one of them isn't and of them yes. - Dec 8th 2011, 08:41 AMPlatoRe: parallelogram - proof
- Dec 8th 2011, 09:23 AMmentaman10Re: parallelogram - proof
ofcurse I know that all the rectangle are parallelogram.

but you can't proof that it is rectangle with out proof it is parallelogram usually...

Anyway, you said both of them can be parallelogram but one of them isn't.

and we don't need to proof here that someone is a parallelogram, we need to proof that some isn't parallelogram. - Dec 10th 2011, 07:57 PMFeryllRe: parallelogram - proof
The issue is that there are multiple representations of quadrilaterals, both parallelograms or not, with one pair of opposite sides being x and a diagonal being y. These constructions you have shown us make it impossible to definitely determine whether or not they're parallelograms, since there are possibilities for both depending on the values of the ambiguities. What I'm led to believe is that you or the teacher left out some angle measures or side lengths or parallel notches.