 # Revision Notes For CBSE Class 9 Math Chapter -5 Introduction to Euclid’s Geometry

The word geometry is derived from the ancient Greek terms which refer to the measurement of the earth. It is a branch of mathematics which mainly deals with the shape, size, area, perimeters, relationships and properties of figures.

Geometry was studied from many ancient civilizations like Greece, Egypt, India, etc. Euclidean geometry is a mathematical system attributed to Alexandrian, a Greek mathematician

Euclidean geometry is the study of plane and solid figures based on five postulates. Listed below are the five basic postulates of Euclidean geometry.

• To draw a straight line from an infinity point.
• To produce a set of straight line.
• To construct a circle with any center and distance.
• To construct a right angle and prove that all right angles are equal to one another.
• To construct the central angles on the same side, less than two right angles on two straight lines.

## Frequently asked Questions on CBSE Class 9 Maths Notes Chapter 5: Introduction to Euclids Geometry

### What is ‘Euclids geometry’?

Euclidean geometry, the study of plane and solid figures on the basis of axioms and theorems employed by the Greek mathematician Euclid.

### What is an ‘Infinity point’?

An ideal mathematical point in projective geometry that preserves the magnitudes of all angles of a transformed plane is called an ‘Infinity point’.

### Who was Alexandrian?

He was a Greek mathematician and engineer who was active in his native city of Alexandria, Roman Egypt.