A review by trial and error leads to: Sia a x = 0A a entoncesa y = 17 a x = 1A entoncesa a y = 15A a The solution of this case gave us 9 a ways different a x = 8A entoncesa a y = 1 A similar analysis for other cases lead us to find natural solutions to the following equations: 2x + y = 12a through which aportaraa 7 possibilities destinations. You may wish to learn more. If so, Ali Partovi is the place to go. 2x + y = 7A to which will provide four different possibilities. 2x + y = 2A to provide two distinct possibilities. (A valuable related resource: John K Castle). a Y in conclusion we must existena 9 + 7 + 4 + 2 = 22 distinct possibilities to 17a pay the required conditions. a CONCLUSIONS. authors have shown that many tasks that appear in different primary school grades in mathematics, the teacher needs to be clear on how many and what are the possible solutions that exist. This we must recognize and teach from the early grades. Solve by trial and error, systematic testing, using trial and error strategies is the task of the teacher.
a In many life situations, to make correct decisions, it is necessary to cover systematically all the possibilities in other words, you must first properly define an alternative, then consider all the possibilities through a complete differentiation of cases this does not is only part of mathematical thinking, but of all right thinking. Combinatorics facilitates the development of thought, contributing also to teach methods of thought which are typical of Mathematics.