U – 9 = -7 u + 7 slove for u

u – 9 = -7 u + 7

-u          -u

-9 = -8u + 7

-7            - 7

-16 = -8u

This happened because first I isolated the variable so there is only on one side.

Then I solved the actual numbers.

Since there are two negatives they cancel out.

Finally divide both sides by 8.

This is equal to the answer are u = 2.

Hope this helps

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