# Area of Circle with Triangles

## Description

"In the triangle above, the line AB is its altitude. Since we know how to find the area of one triangle, we can find the areas of as many triangles as we have made from our circle. Therefore, to find the area of a circle: Find the area of one of the triangles and multiply by the number of triangles." -Foster, 1921

## Keywords

area of circle with triangles, area of triangle, find area of circle, geometry, pie sections, triangles

## Galleries

## Source:

Ellsworth D. Foster ed. *The American Educator (vol. 5)* (Chicago, IL: Ralph Durham Company, 1921)

Courtesy the private collection of Roy Winkelman