URL Rewrite in .htaccess?

i want to use URL rewriting in this link and will apply to all website but it's not work why? and what can i do if i want to using URL rewriting??

the link http://www.example.com/showpage/php?page_id = 98 and i want to be http://www.example.com/showpage/98

i test it in local but not work and test it online in my domain not work. if any tools must run in my domain

<IfModule mod_rewrite.c> 
RewriteEngine On 
RewriteBase / 
RewriteRule ^showpage/$ show开发者_高级运维page.php?page_id=$1 
</IfModule>

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$1 is not defined by a pattern. Try this:

RewriteRule ^showpage/(.*)$ showpage.php?page_id=$1