500 sats \ 3 replies \ @Scroogey 28 Oct \ parent \ on: [Daily puzzle] Proving a curious equality science
Angle units are .
Angle sums in triangles must be 7 (=180°), in quadrilateral 14 (=360°).
Note two pairs of similar triangles. One pair is isosceles.
Ptolemy says
Hence
Equals
Equals
I guess the Ptolemy hint did the trick.
Or maybe with just the figure, you'd have figured it out too...
There are some beautiful other problems in Math Horizons, I'll have to take some time to curate the ones that are easy to post here.
reply
reply
Yeah, with the law of sines, one can get such right angles, but this is basically by constructing a new set of triangles. See #743146
reply