A rectangular shaped stadium whose dimensions are 10 by 20 yards of fencing to enclose it, the stadium will increases the length and width by 3x yards. Find the dimensions of the stadium.

Abank manager wants to encourage new customers to open accounts with principals of at least $2 comma 500. he decides to make a poster advertising a simple interest rate of 3%. what must the principal be if the bank manager also wants to advertise that one can earn $10 the first month? can the poster correctly say, "open an account of $2 comma 500 and earn at least $10 interest in 1 month! "?