URL Syntax for subform with multiple arguments

URL Syntax for subform with multiple arguments

I'm trying to define a function similar to the "Add Attendance," except I want to pass two arguments - one for ID (which works fine by itself) and another one for date (which also works fine by itself).  When I try to combine them together in one URL statement, I don't receive any error messages when I save or execute the script.  However, neither field passes to my form.

This is the URL statement I've keyed:

openUrl("#Form:Add_Distribution?Transaction_Date?Transaction_ID" + input.date + "" + input.id + " ", "popup window", "height=400,width=550");

What's the correct statement when multiple arguments are required?  Thanks!