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**zee-f****Member**- Registered: 2011-05-12
- Posts: 1,220

I am really having trouble answering this question

If I have two lines, will they cross? Explain fully. What postulate helps me answer this question?

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

On a plane. They can be parallel and never meet. They can intersect at 1 point. They can be the same line ( on top of each other ) and intersect at an infinite number of points.

Parallel postulate talks about parallel lines never crossing.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**zee-f****Member**- Registered: 2011-05-12
- Posts: 1,220

So they can and cant? depending on the point or direction ?

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Yes, those are the three possibilites, provided both lines are on a plane.

In the drawing below I have shortened the lines so they look like segments to beter fit them on a screen. Remember as lines they continue on forever.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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