[LOCKED] Date field plus 45 days = (answer in new date field.) Possible???

[#1]

I need a date field to calculate that date plus 45 days, and have the new date populate in another date field.

[#2]

I need a date field to calculate that date plus 45 days, and have the new date populate in another date field.

[#3]

Duplicate of: Adding numbers to dates and have the new date populate in another date field.