The correct answer is - Americans moved west in the 1800's because people wanted to get a fresh start and wanted to be able to buy their own land, as well as to try new economic possibilities, such as farming and gold mining.
In the 1800's the situation in the west started to stabilize and be much more attractive for people to move in. The problems with the native American populations were almost totally put under control so the safety issue was mostly resolved. Also the government had policies to give free land or for very small amount of money as to attract people to move there and thus have the demographic basis for implementing their rule more efficiently. For lots of people, mostly the ones from the lower class, this was seen as a golden opportunity and they used it as quick as possible.
It's 3...
First you add 3 to both sides.(1/3x^2=3)
Then multiply both sides by 3. (x^2=9)
Then take the square root of both sides. (x=+-3)
Finally since it is asking for the positive solution, you can remove the negative sign and so the answer is 3.
