Unfortunately it could be due to a number of different issue. Here are some troubleshooting steps to start with.
Do you see the initial splash screen with the white text on it? If you do, then try loading it into the bios to run hardware diagnostics, and safe mode. Try connecting an external monitor, and see if you get anything. There's also a trick you can try that would release the static buildup from the board, which sometimes causes the issue. Take out the battery (if you can), unplug the power cable. Then hold the power button for 1 minute, next press the power button 10 times. Plug in the power cable and see if the issue is resolved. Lastly, try taking out the battery plugin the power cable and see if it start to work fine. Hope this helps.