The quest of the important in mathematics classroom

In this article, some ideas are exposed to take out profit of the properties of the straight line to know and to explore many interesting properties of functions as polynomials or rational functions. Some ideas are also presented to use the graphic calculators in a sequence that allows integrating the arithmetic language with the graphic and algebraic languages. This proposal has been applied in initial mathematic courses of future economists and engineers, obtaining interesting results related to the development of the graphic thought