Search
Subject Categories:
 Art (456)
 Asperger's (32)
 Blogging (11)
 China and the Han (9)
 eBay (3)
 Education (93)
 Fiction (28)
 Geography (27)
 History (38)
 Humor (49)
 Life (363)
 Mandalas (126)
 Mathematics (1,259)
 Mental Health (74)
 Music (43)
 Mysteries (16)
 Politics (121)
 Quotations (64)
 Religion (58)
 Satire (12)
 Science and Scientists (121)
 Follow RobertLovesPi.net on WordPress.com
MostViewed Posts, Recently:

Recent Posts
 The Eighteenth Stellation of the Rhombicosidodecahedron Is an Interesting Polyhedral Compound
 The EqualEdgeLength, PyramidAugmented Rhombicosidodecahedron
 A Tessellation of Star Octagons, and Two Sizes of Squares
 Nine Circles Imitating a FourLeaf Clover
 The Regular Enneagon, and Three Regular Enneagrams
 An Arrangement of Circles Based on the Euclidean Construction of the Pentagon
 Sunflower
 An Octahedron, Augmented with Eight Great Icosahedra
 A Polyhedron Made of Pentagons, Hexagons, and Octagons
 A Zonohedron Featuring Hexadecagons
Explore RobertLovesPi By Topic
 Arkansas
 Art
 Asperger's
 astronomy
 atheism
 atheist
 chemistry
 chiral
 circle
 cluster
 compound
 cube
 cuboctahedron
 dodecahedron
 dual
 Education
 enneagon
 faceted
 faceting
 geometric
 geometrical
 geometrical art
 geometry
 Golden Ratio
 hexagon
 Humor
 humour
 icosahedron
 icosidodecahedral
 icosidodecahedron
 kite
 life
 mandala
 mandalas
 math
 mathematical
 mathematical art
 Mathematics
 music
 nonagon
 octagon
 octahedron
 op art
 pentagon
 physics
 politics
 polygon
 polyhedra
 polyhedral
 polyhedron
 president
 quotation
 quote
 religion
 rhombi
 rhombic dodecahedron
 rhombicosidodecahedron
 rhombic triacontahedron
 rhombus
 school
 science
 snub dodecahedron
 star
 stellated
 stellation
 symmetry
 tessellation
 tetrahedron
 tiling
 triangle
 Trump
 truncated icosahedron
 USA
 words
 zonohedron
Hit Counter
 347,692 hits
Tag Archives: triangle
Tessellation of Blue Triangles and Yellow Concave Pentagons
Alternately, this can be seen as a tessellation of blue diconcave hexagons and yellow triconcave enneagons. Which do you see?
Posted in Mathematics
Tagged enneagon, geometry, hexagon, Mathematics, nonagon, pentagon, tessellation, triangle
2 Comments
Spectral Golden Spiral II
Image
3 April 2016
Tagged geometry, Golden, Mathematics, rainbow, ratio, spectral, spectrum, spiral, triangle
Leave a comment
Polygons Related to the Golden Ratio, and Associated Figures in Geometry, Part 1: Triangles
There are two isosceles triangles which are related to the golden ratio, [1 + sqrt(5)]/2, and I used to refer to them as the “golden acute isosceles triangle” and the “golden obtuse isosceles triangle,” before I found out these triangles … Continue reading
On Triangle Congruence, and Why SSA Does Not Work
Those who have taught geometry, when teaching triangle congruence, go through a familiar pattern. SSS (sidesideside) triangle congruence is usually taught first, as a postulate, or axiom — a statement so obvious that it requires no proof (although demonstrations certainly … Continue reading
Posted in Education, Mathematics
Tagged angle side side, congruence, congruent, conjecture, counterexample, disproof, Education, geometry, HL, Mathematics, proof, right triangle, school, side side angle, SSA, theorem, triangle
1 Comment
A Polyhedral Demonstration of the Fact That Twenty Times Four Is Eighty
The Platonic solid known as the icosahedron has twenty triangular faces. This polyhedron resembles the icosahedron, but with each of the icosahedron’s triangles replaced by a panel of four faces: three isosceles trapezoids surrounding a central triangle. Since (20)(4) = … Continue reading
Posted in Mathematics
Tagged eighty, four, geometry, icosahedron, Mathematics, multiplication, polyhedra, polyhedron, trapezoid, triangle, twenty
Leave a comment
The 98190 Triangle
In a previous post (right here), I explained the 187290 triangle, derived from the regular pentagon. It looks like this: I’m now going to attempt derivation of another “extraspecial right triangle” by applying halfangle trigonometric identities to the 18º angle. After … Continue reading
Posted in Mathematics
Tagged 98190, geometry, Mathematics, right triangle, special right triangle, triangle, trigonometry
10 Comments