My rectangular soccer field site has a length equal to three times its width. find its area in terms of its length x.

A rectangle with dimensions:

length = a units, and width= b units, has area:  (units squared)

In the rectangular soccer field, the length is x units, which may be meters, feet etc. 

and the length is 3 times the width, so the width is just one third of the length, that is width= x/3  

 square units

  square units

Well in order to lose a pound you would have to burn 1,500 calories. the more calories you burn the more weight you lose. in order to lose 2 pounds you would have to run 4 hours and 28 minutes.