ElectricPavlov

Amount of revenue from ticket sales / # tickets sold = average

[ 20(1.25) + 38(3.50) + 12(4.00) + 50 (5.50)  ]  / ( 20 + 38 + 12 +50)   =~~ $4.01 /tick

Using similar triangle ratios:

6/18  = y/24

y = 24 (6/18) = 8 units

408 m / 24 s = 17 m/s

408 m / 24s   x  60 s /1 min  x 1km/1000m=1.02 km/min

you are given the two roots of the equation    x  =  -3   and   x = 5, so the equation becomes

(x+3)(x-5) = 0        (note the sign change)       Expanded

x^2 -2x-15=0   or 

f(x) = x^2-2x-15   or

y = x^2 -2x-15

Just an FYI:

You should realize that Leap Years only affect the days in Feb    from 28    to 29 in a leap year.    Nothing to do with May.

I would suggest you open an account....it is free.    When 'guests' post questions, responders are less likely to show how the answer was derived....either way...if you do not understand something it is your flippin' responsibility to ask for an explanation.  Most of the time you will get one......

160/400 x 100% = 40% are late....so far

To plaigerize cphill's answer from earlier:

Since the y coordinate of the focus is -2  and the directrix is y = -1  .....the focus lies below the directrix ..

     ...so....this parabola opens downward

The vertex lies 1/2 of the way between the focus and directrix......to find this    we have (0,  [ -2 +  - 1] /2 ) =

(0, -3/2 )    = (h, k)

"p' is the distance between the vertex and focus  =  l -3/2 - (-2) l =   1/2

So....we have the form

4(-p)[ y - k ] = (x - h)^2 

        the sign of 'p' tells us which way the parabola faces......we determined that this is a DOWNWARD facing parabola so    - p   goes in the equation

4(-1/2) [ y - - 3/2)] =  (x - 0)^2

-2 (y+3/2)= x^2    

y+3/2 = -1/2 x^2

y= -1/2 x^2  - 3/2   

Maybe it would be clearer at THIS step:

"p' is the distance between the vertex and focus  =  l -3/2 - (-2) l =   1/2 "      to say p = -1/2 becuase it is a downward opening parabola