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:


The <em>correct answer</em> is:
6 balloons.
Explanation:
Let x represent the number of balloons purchased.
We will call the function for Clowns R Fun c(x):
c(x) = 1.25x+6
We will call the function for Singing Balloons s(x):
s(x) = 1.95x+2
We want the amount for Clowns R Fun, c(x) to be less:
c(x) < s(x)
1.25x+6 < 1.95x+2
Subtract 1.25x from each side:
1.25x+6-1.25x < 1.95x+2-1.25x
6 < 0.7x+2
Subtract 2 from each side:
6-2 < 0.7x+2-2
4 < 0.7x
Divide each side by 0.7:
4/0.7 < 0.7x/0.7
5.7 < x
x > 5.7
She must buy more than 5.7 balloons; the next integer up is 6. She must buy 6 or more balloons.
Answer:

Step-by-step explanation:
Subtract 13 from 17 to get the length of the base. Then add the 1, 1, and 3 together to get the height. Then you use the area formula for a triangle.
To solve this question, you can break it into 2 parts. First evaluate the function g(X)=9x+9 for g(-6). Which is g(-6) = 9(-6)+9 = -45. Then evaluate f(-45). F(-45)= 4(-45)+6= -180+6= -174. The final answer for f(g(-6))= -174.
D. 171
-
Explanation:
4(2+5)^2 - 5^2
4 x 7^2 - 5^2
4 x 49 - 25
196 - 25
171
Answer: D. 171