Two circles, the sum of whose radii is a, are placed in the same plane with their centers at a distance 2a...

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I was employed to survey a field, which I was told was an exact geometrical square, but by reason of a river running through it, I can only obtain partial measurements.

Assume that the human population after the flood was 6 and that 200 years later the population was 1,000,000. Find the annual growth of the population.

Suppose the area of an equilateral triangle be 600. The sides are required.

Download the three winning essays to learn about Kepler's mathematical astronomy, the roots of modern algebra, and the Quadrivium of Isidore of Seville.

A biography of the geometer Donald Coxeter.

The first page of Pathway to Knowledge by Robert Recorde (1510-1558). A version of Euclid's Elements, with commentary by Recorde to make it easier to understand. This page includes Euclid's first three postulates.

A ladder is placed perpendicular to the plane of the horizon, and in coincidence with the plane of an upright wall.

A teacher agreed to teach 9 months for $562.50 and his board. At the end of the term, on account of two months absence caused by sickness, he received only $409.50. What was his board worth per month?

Eratosthenes' measurement of the earth, in a form that's easy for teachers to use in the classroom.