In a Cartesian coordinate system in the plane, the axes divide the rest of the plane into four regions called quadrants. They are numbered as in the figure, with the first quadrant being where x, y > 0.
The numberings of the quadrants
An obsolete navigational instrument used for measuring angles. It consisted of an engraved arc of a quarter of a circle, with a plumb line suspended from the centre of the circle. Stars were sighted along one arm and their elevation was read off the scale against the plumb line.
See Cartesian coordinates.
- method of exhaustion
- method of images
- method of least squares
- method of maximum likelihood
- method of mixtures
- method of moments
- method of moments estimator
- method of steepest ascent
- methodological holism
- methodological individualism
- uranium series
- uranium(VI) fluoride
- uranium–lead dating
- uranium–protactinium dating
- Uranometria
- Uranus
- URAT Catalogue
- Urbain process
- urban
- urban assets
- urban climate
- urban containment
- urban design
- urban diseconomies
- urban dome