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Topic: two-column proof
Replies: 4   Last Post: Nov 11, 1998 3:13 PM

 Messages: [ Previous | Next ]
 Peter Ash Posts: 13 Registered: 12/6/04
Re: two-column proof
Posted: Nov 10, 1998 7:33 PM

TiGER wrote:
>
> I'm working on two-column proofs and I understand how to do it, but it
> is hard having to remember all the theorems, postulates, etc. and apply
> them to the future proofs. I am stuck on this one problem and it looks
> similar to an earlier one I did except for one minor detail. I have
> listed the problem and how far I've gotten and the similar problem I
> have done.
>
> Don't worry, no pop-ups on this page. At least not with Netscape or
> Internet Explorer.
>
> http://www.geocities.com/SouthBeach/Inlet/2101/

In your Web page, you say:

I had worked through a similar problem as this, only I had to prove that
Triangle TRP is congruent to TRQ.

Just step back and think about that. If two triangles are congruent,
that means they have the same shape. In fact, you must have proved a
theorem which says that if two triangles are congruent (or even
similar), then their corresponding angles are equal. And isn't that what
you are trying to prove?

The hardest thing for students to learn about geometry proofs is that,
except for the simplest, you have to think about the geometry. If you
just try to stick a bunch of givens and theorems together, you will get
lost when the problems get harder.

Good luck with future problems,
Peter

Date Subject Author
11/10/98 TiGER
11/10/98 Peter Ash
11/11/98 TiGER
11/11/98 TiGER
11/11/98 Walter Whiteley