Talk:Congruence (geometry)

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Contents 1 A handy mnemonic 2 Equality 3 SSA 4 Politically charged statement 5 Congruent angles?

[edit] A handy mnemonic

An easy way to remember that SSA (Side-Side-Angle) does not prove congruence for triangles is to simply reverse the order of the letters. --Jediknil

[edit] Equality

"In less formal language, two sets are congruent if they have the same shape and size, but are in different positions (for instance one may be rotated, flipped, or simply moved)."

Should we specify two different sets? Every set is congruent to itself.--Syd Henderson 01:16, 22 September 2006 (UTC)

[edit] SSA

Should we include a diagram showing how SSA doesn't work? Just a suggestion. Altopian

asa sas sss are congruence theorem but ass aaa saa aas are not

[edit] Politically charged statement

I don't think that the word "infamous" belongs in the phrase "the infamous SMSG system". Having both learned my geometry from SMSG and taught geometry, I wish that book would come back. The textbooks currently available attempt to be rigorous but are sorely lacking. In fact, the last time I taught geometry, I tracked down a copy and taught from photcopies.

[edit] Congruent angles?

I have altered two occurrences of congruent to equal. In cautious standard usage, angles are never congruent,nor are sides. They are equal, and their being equal is a necessary condition for a pair of figures to to congruent. See major British and American dictionaries: SOED, and Webster's Third International ("2 geometry : superposable so as to be coincident throughout"). See Congruence (geometry).

I see that there is an external link mentioning "congruent" angles; I have left that as it is, but its usage should not affect the accuracy of Wikipedia's own text.

– Noetica^♬♩ Talk 20:46, 10 December 2007 (UTC)