When adding and subtracting rationals, what should be the first thing you find? How do you find it?

Typically you should factor the denominators first, as it will make getting the least common multiple easier. For the first denominator, you can factor out x^2, the second denominator is a perfect square, (x^2+1) (x^2-1) and the last denominator is already simplified. It appears the denominators don't have a common factor though, so yes, you would have to multiply each of the denominators out.

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

72 is the answer to this problem