I have a 29day cycle and had sex on the 6th,11th,12th,15th,19,and the 21th,but my cycle came on on the 19th and went off on the 23rd/24th.What day did I get pregnant?

One of them, it is not that exact, is there a reason you have to know an exact day ?

Unless you know for sure when you ovulated, no one can tell you.

All women are different.

If this is a question of paternity than you'll have to wait until the child is born, get a DNA test.

If this is to pinpoint when you'll deliver, delivery dates are hit and miss, so knowing the exact date you got pregnant won't help a lot. Only around 10% of women deliver on their due date anyway.