Solve number 9 using quadratics

     5f² - 3f = 8
5f² - 3f - 8 = 0
f = -(-3) +/- √((-3)² - 4(5)(-8))
                     2(5)
f = 3 +/- √(9 + 160)
               10
f = 3 +/- √(169)
            10
f = 3 +/- 13
         10
f = 3 + 13      f = 3 - 13
        10                 10
f = 13            f = -10
     10                   10
f = 1.3           f = -1

Formulas for marine are 28 gallons per teaspoon.  30gal (28t/1gal) the gallons cancel leaving teaspoons = 840 teaspoons there are 8floz = 1cup 1floz = 2 tablespoons 3t = 1 tablespoons it's 31.11111111111111. so if you round to the nearest cup it would be 31. idk if this but i'm sure it will.