Display most recent posts in category with Twenty Ten theme widget

I am fairly new to WordPress, and I would like to have a list of the most recent posts in a certain category appear in a right-hand panel (I can do this with all posts, but not specific categories)

I am using the Twenty Ten theme, on wordpress.com. I have found the following code, but unsure if or where this can be added:

ul
?php $recent = new WP_Query("cat=10showposts=5"); while($recent-have_posts()) : $recent-the_post();?
    lia href="?php the_permalink() ?" rel="bookmark"?php the_title(); ?/a/li
    ?php endwhile; ?
/ul

Topic theme-twenty-ten sidebar categories posts Wordpress

Category Web


You are using wordpress.com. You cannot modify your Theme template files, or upload Plugins. You are limited to the Plugins available via Dashboard -> Plugins.


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