Enable button when checkbox is checked not working

Enable button when checkbox is checked not working

I am trying to implement a validation on a submit button on click of a checkbox.
I tested my code on a webpage I saw online and it worked but
all efforts to get it working on my page failed (including using pure JavaScript).
I noticed that the checkbox's name was not included in the intellisense but the submit button was displayed.

I'm using jquery 1.1.1.min.js and jquery mobile 1.7.2

Please help, I'm stuck.