Answer:
[Vertex form]
Step-by-step explanation:
Given function:
We need to find the vertex form which is.,
where 
represents the co-ordinates of vertex.
We apply completing square method to do so.
We have
First of all we make sure that the leading co-efficient is =1.
In order to make the leading co-efficient is =1, we multiply each term with -3.
Isolating 
and 
terms on one side.
Subtracting both sides by 15.
In order to make the right side a perfect square trinomial, we will take half of the co-efficient of term, square it and add it both sides side.
square of half of the co-efficient of term = 
Adding 36 to both sides.
Since 
is a perfect square of 
, so, we can write as:
Subtracting 21 to both sides:
Dividing both sides by -3.
[Vertex form]
Soup b; no
soup c; yes
soup d; no
soup e; yes
Emily gave Jake 20% of the buttons. 20% = 15 buttons, and 15 x 5 = 75
First of all, we compute the points of interest, i.e. the points where the curve cuts the x axis: since the expression is already factored, we have
Which means that the roots are
Next, we can expand the function definition:
In this form, it is much easier to compute the derivative:
If we evaluate the derivative in the points of interest, we have
This means that we are looking for the equations of three lines, of which we know a point and the slope. The equation
is what we need. The three lines are:
This is the tangent at x = -2
This is the tangent at x = 0
This is the tangent at x = 1
If this is the case, then you know by the polynomial remainder theorem that
is a factor of
, so there is some polynomial
such that
