Matematiki

[Richard M. Robin]

I have agreed to post this message for Betty Leaver. She is a SEELANGS
subscriber, but has had trouble getting her post to "stick":

Are there any mathematicians among SEELANGers?  I need a translation of
the phrase: priznaki ravenstva triugolnikov.  I don't need a literal
translation or an explanation.  I need the term used by American high
school teachers of geometry -- one that such teachers would instantly
recognize.  I have checked geometry books and cannot seem to find a set
phrase that would match.  However, my knowledge of geometry is thirty
years old.  Can anyone help?  If yes, please contact me at
Leaver at AOL.COM.  Thanks, Betty Lou Leaver