A triangular park has side lengths of 3x + 7, 20x and 2(x – 4). Write a simplified expression to represent the perimeter of the park.

I explore this idea a bit. obviously x < 5 (because 5-x has to be positive.

2x-5 > 0 is a requirement, also, so x > 2.5 is required

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