how to remove sidebar in one page (2013)

Hello people. I have searched for an answer to this question and all answers are years old. All them talk about creating a template “copy page.php, add some lines, remove sidebar calls, etc”, but when I open the page.php im my theme folder I got only three lines:
<?php get_header(); ?>
<?php get_template_part( ‘loop’, ‘page’ ); ?>
<?php get_footer(); ?>

it is the same with index.php, so where can I remove the sidebars in just one page. Or maybe there is a plugin to disable (completely) the sidebar ? all plugins I tried just remove widgets but not the whole sidebar (You always get the default one as minimum).

Thanks in advance
Eduardo