Call to undefined function imagecreatefromjpeg()
It appears the page you were looking for doesn't exist. Sorry about that.
Back end appears to work fine.
I did notice one oddity (this may be a red herring) - the quickstart install warned that display_errors is on. I checked my php.ini and it is set to off, but testing with php <?php echo get_ini('display_errors'); ?> returned no value.
I've previously installed Joomla 3.5 with sample data on this server with no problem, it is also running a copy of my live Joomla site. Each Joomla install has a separate folder and uses the same MySQL database with different table prefix setting.
Tech details - Server is Ubuntu 16.04, Apache, PHP 7.0