Pretty please help me:)

Step-by-step explanation:

a. Yes is proportional with the cost because they depend on one another

b. (0,0) means if we buy 0 cookies we pay $0

c. (1, 0.50) means that if we buy 1 cookie we have to pay $0.50

d. the unit rate is how much we pay for one cookie so is $0.50 per 1 cookie

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this

the answer is here: : )

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