ElectricPavlov

Your Q is missing something.....   is that SUPPOSED to be   y = 20 x    ???

Here is a graph of y = 20

https://www.desmos.com/calculator/qgdd7pe1ab

Here is a graph of y = 20x

https://www.desmos.com/calculator/myz9mbyjc6

Boy one rec'd   5 out of  (5+3)     or    5 /8 ths of 4000          5/8 * 4000 = _________

   the other boy received  3/8 x 4000 = _________

For Part D  .....   do you know how to do derivatives ?

f(6) = 24  

find the slope at this point (6) by using the derivative

   f ' (6) =   2x -2   = 10   = m        

   now you have a slope  m = 10    and a point    (6,24)     to derive the equation of the line......

The product of a constant factor 12 and a 2-term factor x + 3

36 bars / day  *  10 days   = 360 bars  

If you knew the answers to A and C.....WHY did you post them???????

For part B....you do it just the same way...with slightly different numbers ...

f(6) = 24

f(6+h) =   h^2 + 12h + 36 - 12-2h = h^2 + 10h + 24

The slope between the points becomes   (y1-y2)  / (x1-x2) 

(h^2+10h+24  -24) / (6+h - 6) =   (h^2 + 10h ) / h     =   h+10              (check my math.....but that is how you do it.....)

58 = 12 + 2 p     solve for p, the price of a pass

2 2/3 doz = 32

1 doz       = 12

2 1/3 doz = 28                GCF  of   32  12   28   =  4   bags

x = smaller number

l = larger number = x + 9             summed, they equal 47

x      +      (x + 9)      =   47               solve for 'x'    the smaller number