A responsible estimate of a 20% tip on a $33 meal

Aformual for 8 bottles of window cleaner calls for 6 cups of rubbing to customers alcohol 2 1/4 gallons of water and 1 1/2 cups of ammonia alcohol would the forula call if a factory made 1,280 bottles for stores to sell to customers

Describe the 2 algebraic methods you can use to find the zeros of the function f(t)=-16t^2+400.

Idon't get undoing if its pass adding and subtracting so can someone ? x-2 over 5 = 18