MGMAT - parallelogram

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MGMAT - parallelogram

by marcusking » Thu Apr 30, 2009 8:16 am
In the quadrilateral PQRS, side PS is parallel to side QR. Is PQRS a parallelogram?

(1) PS = QR

(2) PQ = RS

OA is A but I think it should be D.

If we know that PS || QR then if PQ = RS shouldn't PQ || RS also? I've tried to sketch it to get it to be wrong but I can't come up with any situation where it doesn't make a parallelogram.

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by mike22629 » Thu Apr 30, 2009 8:39 am
Its hard to explain without a diagram.

PS ll QR

Obviously you see that A is sufficient

I will try a diagram this way, not sure how it will turn out


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As you can see the two parellel lines (PS and QR) can produce two lines of equal length that are not parellel. Hence, it is not a parellogram.
That is only possible if PQ not equal PS. If they are equal, only a parrellogram is possible.

IMO A

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by mike22629 » Thu Apr 30, 2009 8:40 am
Lol didnt turn out well.

To explain it:

Imagine two 45/45/90 triangles on opposite sides of a square facing the opposite direction. That was the shape I was trying to illustrate.

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by marcusking » Thu Apr 30, 2009 8:54 am
mike22629 wrote:Lol didnt turn out well.

To explain it:

Imagine two 45/45/90 triangles on opposite sides of a square facing the opposite direction. That was the shape I was trying to illustrate.
Thanks for trying. I think I finally was able to envision what it would look like
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