René Descartes

Yes, he did. He devised the Cartesian coordinate system which led to analytical geometry.

Rene Descartes was a French mathematician and in the early 17th century he introduced what we call today the Cartesian coordinate plane in which graphs are plotted.

Rene Descartes is regarded as the father of Western philosophy. His writings influence most of the subsequent writings in Western philosophy.

Descartes explains the logic behind the laws of reflection he discovered in his work "Dioptrics". He uses the idea of a tennis ball bouncing at an angle of the ground and up through a sheet to formulate the laws of reflection on a geometric plane.

solved pi...

He thought about philosophy and science.

Rene Descartes described analytic geometry in 1637, in an appendix to his Discourse of Method. The coordinate plane idea's origin is uncertain, and may date back to Menaechmus, a Greek mathematician from the 4th century B.C. Please see the related links for details.

Descartes used the parabola to illustrate algebraic equations. He put these equations on a visible plane using the Cartesian coordinate system and they sometimes took the shape of a "u" curve, or a parabola.

Rene Descartes initiated the process in which algebra is thought upon. His major contribution was making me have to do this pointless essay.

Joachim Descartes

The wording of this question implies that you already know of some subjects in which Descartes contributed, and want to know what else he did. However, we have no way of knowing what you know and so cannot answer the question.

1630s

he's work for a teacher

His main philosophical contribution was "cogito ergo sum" which translates to "I think therefore I am".

Of course he did. He was a rational human being.

he actually didn't discover it

rené Descartes is pronounced "reh'ney dey-kart'

Descartes had one daughter.

It was the French mathematician Rene Descartes.

Rene Descartes developed the rectangular coordinate system.

Rene Descartes was a French mathematician who introduced coordinated geometry in which shapes and straight line equations are plotted on the Cartesian plane.

Descartes didn't really 'discover' things. He was a philosopher and mathematician. He is known, amongst other things, for developing the cartesian system of co-ordinates (the xy system we usually use for graphs), founding rationalist philosophy, for his work on optics, and for laying the mathematical foundations for the development of the calculus.

He was considered the father of Western philosophy: much of Western philosophy written since his time was influenced by his writings.

Gomene, I am also searching for the answer so I thought that the answer would be here and I didn't actually think I am the one who will suppose to answer this