Why did many amercans move west in 1840s?

I think to gain more fertile land, because there was a shortage of it in the east back then.
P.S. I remember you, I answered one of your questions already...

Concurrent jurisdiction is the ability to exercise judicial review by different courts at the same time, within the same territory, and over the same subject matter. for instance, a domestic violence matter may be heard in either a general civil court or a family court in the same county.i hope that this you : )