[RustyBrooks]

If you're going to use your likely equity to call on 5th, you have to, at least, make an estimation of how much more you'll have to put into the pot, and how big it'll be. Those are your effective pot odds and you can try to use them to make a decision on 5th.

If I know the opponents hand, or have a pretty good idea, I prefer to look at
* my chances of pulling ahead the next card (assuming that I'll be pulling far enough ahead, or my redraw is great. Like if he has a J and I'm drawing to a T9 then I am not really going to be looking at the odds to improve on the next hand, I'll check out my equity. If he has a J and I'm drawing to a T6 then that can be another story because I have possibilities to improve beyond the next card)
* my chances of drawing a card on the next street that will make him fold. This doesn't really apply to a hand like this one, because if I catch good and he bricks on 6th, he's probably not going to fold. But in a situation where I have an apparent 4-card hand and so does he, if I catch a low card, even one that pairs me in the hole, and he bricks, the chances of him folding go way up, especially if my board is lower than what he's drawing to.

Anyway, effective-odds wise, the player is probably going to have to put $12 in to win $35 (2:1) to see 7th (I assume he folds unimproved, otherwise it's $18 into a $41 pot (1.2:1). So his effective odds blow assuming villain bets every street. If he gets a free 6th st or something maybe it's OK.

This is assuming I did my math right. I'm thinking when you say the pot is $29 you mean after villain bets. So, to see 7th, hero is going to have to put in $6 on 5th and 6th and villain will put in $6 on 6th (put in 6+6 to win 29+6). To call 7th if villain bets, hero puts in 6+6+6 to win 29+6+6

Using effective odds on 5th can be hard though because it's difficult to know whether villain will bet every street, whether he'll pay off a bet/raise/check-raise on the end if you hit well, etc.