Amathematical system created by this man; idea of locating a point where two lines come together

The Cartesian Coordinate System was invented by Rene Descartes back on the 17th century. It uses a pair of perpendicular axis to measure the distance from the origin (where the axis meet) to an specific point on the plane.

It's the basis for the analytic geometry and also provides an excellent interpretation of many of the other disciplines of math via the graph of a function. It's also the most used system in astronomy, physics and engineering.

in contrast, the biological controls are self-sustaining, inexpensive and very effective once established. biological control could be used on thousands of golf course acres, improving their biodiversity and quality as wildlife habitat. in the process, the golf industry will be shown to be leaders in an environmental stewardship program of benefit not only to the lands they manage but also to the watersheds in which they exist.

ayatollah khomeini can best be described as the leader who declared iran to be an islamic republic.