RS Aggarwal Solutions for Class 9 Chapter 6 “Introduction-to-Euclid-s-Geometry”, Euclidean geometry is the study of geometrical shapes and figures based on different axioms and theorems. This part of geometry was employed by the Greek mathematician Euclid, who has also described it in his book, Elements. Therefore this geometry is also called Euclid geometry. The postulates and axioms which were introduced by Euclid are used primarily for arithmetic and measurement. Euclidean geometry, the study of plane and solid figures based on axioms and theorems employed by the Greek mathematician Euclid (c. 300 BCE). In its rough outline, Euclidean geometry is the plane and solid geometry commonly taught in secondary schools. Euclid’s Geometry has applications in various fields like Astronomy, Navigation, Surveying, Artistic Designs, Computer-Aided Design, Architecture, Computer-Aided Manufacturing and Classical Geometrical Problems. The Chapter explains some of the significant concepts like Axioms and Postulates, Euclid’s five postulates and finding the number of lines passing through two given points.