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Which are the parallel lines? alt text

I prove that $a$ and $b$ are parallel but can't prove that $c$ and $d$ are parallel. The angles, which are $135^o$ and $45^o$ are alternate angles.They aren't equal , so $c$ isn't parallel to $d$ but the answer is that $c$ is parallel to $d$. Am I right that they aren't?

Edit: They are a little inclined like these: http://www.math10.com/f/download/file.php?id=1169

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    To put it simply, yes. If the answer is that they are parallel, I suspect there is more to this than your description allows.2010-11-14
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    Moreover, if the angles are how you say they are, then $C$ and $D$ are perpendicular...2010-11-14
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    Could you please post or link to the full original problem for reference?2010-11-14
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    Have you tried making an *accurate* drawing?2010-11-14
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    @Carter , they aren't perpendicular.My drawing is wrong.2010-11-14
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    @J.M they are a little inclined.2010-11-14
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    Note that $135+45=180$.2010-11-14
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    @Filmus ,yes but they must be adjacent angels to do this ,mustn't they?2010-11-14
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    @lam3r4370, draw the picture accurately and you will see that $C$ and $D$ are, in fact, perpendicular to one another. This is not based on the drawing, but on the angles that you gave.2010-11-14

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