Question

what is coordinate geometry

Answer 1

Coordinate geometry is one of the most important and exciting ideas of mathematics. In particular it is central to the mathematics students meet at school. It provides a connection between algebra and geometry through graphs of lines and curves.

Answer 2

Assume you are a teacher/professor. In a classroom full of students whom you've never met, how would you ask a particular student to stand up and answer your question? There may be many ways, few of them are:

Point your finger towards that student.
Walk towards his or her seat.
Say something like "the person sitting in the 4th row and 5th column", or "the person sitting in the left corner", or "the first student in the second last bench".

While method 1 is used quite often, it is not perfect for obvious reasons. However, if someone uses method 3 to point out a student (which is more precise), he or she is inadvertently using the principles of Coordinate Geometry.

Coordinate Geometry is nothing but naming a point (student, in our case) based on his position from the axis (walls, in our case).