In a present paper a problem of classification of Aff(2, R)orbits' dimensions is considered on example of an autonomous two-dimensional affine differential system of first order. Methods of Lie algebras are used in the work, as well as methods of group analysis. Computer algebra systems "Bergman" and "Mathematica 5.0" are widely used. Mathematics Subject Classification 2000: 34C14, 34C05, 58F14. Keywords and phrases: Differential equation, Lie algebra, affine invariant, Aff(2, R)-orbit.
E. Naidenova