Answer:
The equation has a maximum value with a y-coordinate of -21.
Step-by-step explanation:
Given

Required
The true statement about the extreme value
First, write out the leading coefficient

means that the function would be a downward parabola;
Downward parabola always have their vertex on top of the parabola and as such, the function has a maximum value.
The maximum value is:

Where:

So, we have:



Substitute
in 


<em>Hence, the maximum is -21.</em>
Answer:
Yes
Step-by-step explanation:
Let's take any random multiple of 4 as an example:
8 = 2 • 4
64 = 2 • 32
20 = 2 • 10
Try any multiple of 4—this pattern continues.
Answer:
Slope = 2
Step-by-step explanation:
Slope = 20/10 = 2