Describe the number ofcards y and have after x weeks y=4x+2

I'm not sure what you're trying to ask but,

in 1 week, y will have 6 cards. 6=4 (1) + 2

in 2 weeks, y will have 10 cards. 10=4 (2) + 2

in 3 weeks, y will have 14 cards. 14=4 (3) + 2

you basically just substitute in the number of weeks with x and then just solve the problem to find out the total number of cards