In geometry, two triangles are said to be 5-Con or almost congruent if they are not congruent triangles but they are similar triangles and share two side lengths (of non-corresponding sides). The 5-Con triangles are important examples for understanding the solution of triangles. Indeed, knowing three angles and two sides (but not their sequence) is not enough to determine a triangle up to congruence. A triangle is said to be 5-Con capable if there is another triangle which is almost congruent to it. The 5-Con triangles have been discussed by Pawley:, and later by Jones and Peterson. They are briefly mentioned by Martin Gardner in his book Mathematical Circus. Another reference is the following exercise Explain how two triangles can have five parts (sides, angles) of one triangle congruent to five parts of the other triangle, but not be congruent triangles. A similar exercise dates back to 1955, and there an earlier reference is mentioned. It is however not possible to date the first occurrence of such standard exercises about triangles. (Wikipedia).

Geometry - Ch. 5: Triangle (1 of TBD) What is a Triangle?

Visit http://ilectureonline.com for more math and science lectures! To donate: http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will learn the definition of a triangle is a geometric shape that has 3 sides and 3 angles. Next video in this series on YouTube:

From playlist GEOMETRY CH 5 TRIANGLES

What are four types of polygons

๐ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

๐ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

Geometry - Ch. 1: Basic Concepts (28 of 49) What are Convex and Concave Angles?

Visit http://ilectureonline.com for more math and science lectures! In this video I will explain how to identify convex and concave polygons. Convex polygon: When extending any line segment (side) it does NOT cut through any of the other sides. Concave polygon: When extending any line seg

From playlist THE "WHAT IS" PLAYLIST

Geometry: Ch 4 - Geometric Figures (8 of 18) The Regular Pentagon

Visit http://ilectureonline.com for more math and science lectures! In this video I will find the 3 angles of the regular pentagon and its parameter and area. Next video in this series can be seen at: https://youtu.be/3G_jjW1d280

From playlist GEOMETRY 4 - GEOMETRIC FIGURES

What is the difference between convex and concave

๐ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

How to label triangles depending on the length of their sides

๐ Learn all about classifying triangles. A triangle is a closed figure with three sides. A triangle can be classified based on the length of the sides or based on the measure of the angles. To classify a triangle based on the length of the sides, we have: equilateral (3 sides are equal), i

From playlist Triangles

Classifying triangles by the measure of their sides

๐ Learn all about classifying triangles. A triangle is a closed figure with three sides. A triangle can be classified based on the length of the sides or based on the measure of the angles. To classify a triangle based on the length of the sides, we have: equilateral (3 sides are equal), i

From playlist Triangles

!!Con West 2019 - Michael Malis: Generating fractals โฆ with SQL queries!!!

Presented at !!Con West 2019: http://bangbangcon.com/west SQL databases can do a lot. They are fantastic at making it easy to work with large amounts of data. One of the lesser-known capabilities of SQL databases is that they can be used to generate fractals! In this talk, weโll take a l

From playlist !!Con West 2019

I. Pasquinelli - Deligne-Mostow lattices and cone metrics on the sphere

Finding lattices in PU(n,1) has been one of the major challenges of the last decades. One way of constructing a lattice is to give a fundamental domain for its action on the complex hyperbolic space. One approach, successful for some lattices, consists of seeing the complex hyperbolic spa

From playlist Ecole d'รฉtรฉ 2018 - Teichmรผller dynamics, mapping class groups and applications

Live Stream #161: Chaos Game & Quick, Draw! API

In this live stream, I code the Chaos Game, which is inspired by my visit at Thinkercon. Plus, I use the Quick, Draw! API to get drawings from the Quick, Draw! dataset. ๐ https://thecodingtrain.com/CodingChallenges/123.1-chaos-game ๐ https://thecodingtrain.com/CodingChallenges/123.2-chaos

From playlist Live Stream Archive

Geometry: Ch 3 - Names & Symbols (5 of 8) Triangles

Visit http://ilectureonline.com for more math and science lectures! In this video I will define and explain the differences of right, obtuse, acute, congruent and similar triangles. Next video in this series can be seen at: https://youtu.be/LVluSflQK0c

From playlist GEOMETRY 3 - NAMES & SYMBOLS

Outliers : Data Science Basics

How do we deal with outliers in data science? My Patreon : https://www.patreon.com/user?u=49277905

From playlist Data Science Basics

Your ACT math prep should be first to focus on mastering algebra 1, geometry and algebra 2. Once you have these course levels mastered you can then move onto test taking tactics and practice ACT questions. If you need math help in studying math for the ACT check out my ACT Math Prep Course

From playlist Test Prep Math

Tropical Geometry - Lecture 9 - Tropical Convexity | Bernd Sturmfels

Twelve lectures on Tropical Geometry by Bernd Sturmfels (Max Planck Institute for Mathematics in the Sciences | Leipzig, Germany) We recommend supplementing these lectures by reading the book "Introduction to Tropical Geometry" (Maclagan, Sturmfels - 2015 - American Mathematical Society)

From playlist Twelve Lectures on Tropical Geometry by Bernd Sturmfels

NO TRIGONOMETRY ALLOWED!! ๐ค๐ค๐ก Plane geometry problem solving

Two very nice geometry problems sent in by a subscriber. Thank you for watching! *I forgot to mention on the second question how investigating the special case of an isosceles triangle, while it did not help me prove the general case, did help me think about how I might come up with a sol

From playlist Problem Solving

Coding Challenge #123.1: Chaos Game Part 1

In this multi-part coding challenge, I visualize the "Chaos Game". Code: https://thecodingtrain.com/challenges/123-chaos-game p5.js Web Editor Sketches: ๐น๏ธ The Chaos Game Part 1: https://editor.p5js.org/codingtrain/sketches/BJqKF9KRQ ๐น๏ธ The Chaos Game Part 2: https://editor.p5js.org/codin

From playlist Coding Challenges

Amit Patel (5/1/21): Edit Distance and Persistence Diagrams Over Lattices

We build a functorial pipeline for persistent homology. The input to this pipeline is a filtered simplicial complex indexed by any finite lattice, and the output is a persistence diagram defined as the Mobius inversion of a certain monotone integral function. We adapt the Reeb graph edit d

From playlist TDA: Tutte Institute & Western University - 2021

Geometrical Snapshots from Ancient Times to Modern Times - Tom M. Apostol - 11/5/2013

The 23rd Annual Charles R. DePrima Memorial Undergraduate Mathematics Lecture by Professor Tom M. Apostol was presented on November 5, 2013, in Baxter Lecture Hall at Caltech in Pasadena, CA, USA. For more info, visit http://math.caltech.edu/events/14deprima.html Produced in association w

From playlist Research & Science

Determine if a polygon is concave or convex ex 2

From playlist Classify Polygons