There are tons of ways to answer this question each with its own benefits. Lets check out a few.
The very first line of the output shows the version. Then it shows all the registered commands. Need only the version? Use
--version when running the command.
composer show | grep laravel/framework
This will search the output of all installed packages and only show the Laravel framework.
composer show -- laravel/framework
This will show the version and a bunch of additional information like license, description and dependencies.