Why Do We Use Coordinate Geometry?. Euclid’s Elements (about 300 B.C.). http://www.claymath.org/euclid/. Euclidean Geometry. Euclid was a Greek philosopher (c. 330 BC to 275 BC) Euclidean geometry analyses shapes like points, lines, and circles
Descartes used algebra to describe points, lines, and circles geometrically using a coordinate system
y = x2
..at 91, this gentle scholar can recall every racist rule he ever tackled: the "No-Negroes" housing complex where he pushed to have blacks made welcome; the all-white math conferences to which he insisted on bringing black professors; the all-black grade school where he tried to enroll his daughter….These fights lost him a string of jobs and in time got him blacklisted altogether for the "un-American" activity of championing racial equality, driving him to leave his homeland for Canada where he was in fierce demand as a math whiz.
The Toronto Star, Jan 15, 2007