The extensions have the software and sample configuration files. Did you enable PHP in your httpd.conf file? Have you enabled server-info in your httpd.conf file? If so does it show the PHP module, like this:
Module Name: mod_php.c
Content handlers: yes
Configuration Phase Participation: Create Directory Config, Merge Directory Configs
Request Phase Participation: Content Handlers
Module Directives:
php_value - PHP Value Modifier
php_flag - PHP Flag Modifier
php_admin_value - PHP Value Modifier (Admin)
php_admin_flag - PHP Flag Modifier (Admin)
PHPINIDir - Directory containing the php.ini file
Current Configuration: