Area of Triangle

“Fig. 3 shows triangle I = triangle II, III = IV, and so triangle ABC = 1/2 of rectangle ABDE. The fact is realized that the area of a triangle equals 1/2 the product of the base and altitude.” -Foster, 1921

Keywords

rectangle, right triangles, equal triangles, triangle area, half base times height

Galleries

Miscellaneous Triangles

Source

Ellsworth D. Foster ed. The American Educator (vol. 1) (Chicago, IL: Ralph Durham Company, 1921)

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