Answer: Option D

Step-by-step explanation:
Note that the projectile height as a function of time is given by the quadratic equation

To find the maximum height of the projectile we must find the maximum value of the quadratic function.
By definition the maximum value of a quadratic equation of the form
is located on the vertex of the parabola:

Where 
In this case the equation is: 
Then

So:


This is a difference of squares problem. You just have to make sure every term is a perfect square and that there is subtraction in the problem.
Answer:
Step-by-step explanation:
11 t= -5 17 r = 27
12 n= -1 18 k = -20
13 m=-5
14 x= - 11
15 y = 70
16 f = - 70
Answer:
C. 
A. First Picture
Step-by-step explanation:
We are given the inequality,
.
On simplifying the inequality, we get,

i.e. 
i.e. 
i.e. 
So, we get the correct representations of the inequality are,
C. 
A. the First Picture