This study exam the effects, in the value of the company, of different proportions of funds that finance an investment's project. The finance theory about capital structure says that different proportions of capital, the ratio debt/equity, don't affect the value of the company. The paper aims to exam the effects of different ratios of debt and equity as a funding of a hypothetical project selected by PETROBRAS - Petróleo Brasileiro S.A., by simulations, and to determine what is the ratio that maximizes the value of de firm. The subject is important for financial managers, financial analysts, investors, lenders, consultants e and researchers, especially because the economic situation of the country. We have developed the theme with the explicit definition of the problem, hypothesis, objectives, methodology, review of referential theory, an example and the conclusions of the study.The conclusions have indicated the possibility of managing the capital structure to finance a new project in order to maximize the value of de firm.
new investment's projects; financial decisions; capital structure; debt and equity; value of the firm
