I am confused on how weighted courses work.

At my school, a two semester course is weighted (1.2) and a semester course is weighted (.6)
How do these numbers help your gpa?

If you earn a 4.0 in a semester class, then it goes into your GPA as 0.6 * 4 = 2.4 If you earn a 4.0 in a two-semester-class, then it's 1.2 * 4 = 4.8.

Classes that aren't weighted are 0.5 for one semester, and 1.0 for two semesters. You earn more points in weighted classes.