How to view path of Dock Icon
Simply hold the Command key when you click the app in the dock and it will open the location of the app rather than opening the application as normal. Once you have the app open in finder you can right click the name of the folder at the very top of the finder window that opened and it will show the path to the app. 

Alternatively you could right click the app in the finder window and click "Get Info" to show a panel like this with the path to the app: