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Introduction References & Edit History Related Topics
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Standard lettering of a triangle Area of a triangle Pythagorean theorem Three theorems of congruent triangles Figure 6: Construction for similar triangles (see text). Contrasting triangles in Euclidean, elliptic, and hyperbolic spaces. Fundamental theorem of similarity Chinese and Greek geometric theorems triangle inscribed in a circle Figure 9: If the angles of triangle ABC (representing any triangle) are trisected, then triangle DEF is equilateral.
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Thanksgiving Turkey with all the sides
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Santa Claus flying in his sleigh, christmas, reindeer
Was Santa Claus a Real Person?
Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that
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Diverse elementary school children wearing school uniforms running outside of school. Boys girls
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Close up of books. Stack of books, pile of books, literature, reading. Homepage 2010, arts and entertainment, history and society
12 Novels Considered the “Greatest Book Ever Written”
Thanksgiving Celebration Traditional Dinner Setting Food Concept
Why Is Thanksgiving in the U.S. Celebrated on a Thursday?
Mayer Amschel Rothschild (1744-1855), founder of the house of Rothschild; lithograph by Friedrich Lieder, c. 1830.
Where Do Anti-Semitic Conspiracy Theories About the Rothschild Family Come From?

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Photos

Standard lettering of a triangle
Area of a triangle
Pythagorean theorem
Three theorems of congruent triangles
Figure 6: Construction for similar triangles (see text).
Contrasting triangles in Euclidean, elliptic, and hyperbolic spaces.
Fundamental theorem of similarity
Chinese and Greek geometric theorems
triangle inscribed in a circle
Figure 9: If the angles of triangle ABC (representing any triangle) are trisected, then triangle DEF is equilateral.
See All Images →

Related Topics and References

Topics

Key People

Heron of Alexandria
Greek mathematician