Answer: The vertex of the parabola (quadratic function) is (-2,-4)
Fourth option: (-2,-4)
Solution:
y=x^2+4x
y=ax^2+bx+c; a=1, b=4, c=0
Vertex: V=(h,k)
h=-b/(2a)
h=-4/(2(1))
h=-4/2
h=-2
y=x^2+4x
k=y=h^2+4h
k=(-2)^2+4(-2)
k=4-8
k=-4
Vertex: V=(h,k)
Vertex: V=( -2, -4)
The answer would be A) 2,640.
In order to find this we must first find an amount of people per square feet. Since we are given that 10 people fit in a 5x5 square, we know that 10 people fit in 25 square feet. This will be the basis for our final calculation.
Now we need to find how many square feet we have. Since it is a quarter of a mile long, we'll divide the number of feet in a mile by 4.
5,280/4 = 1320.
Now we take the length and multiply it by the width, which is 5ft.
1320 * 5 = 6,600 square feet.
So we now know the size of the crowd. We can use that and multiply it by the factor that we found at the start to find the number of people.
6,600 square feet * 10 people/ 25 square feet = 2,640 people.
Answer:
D
Step-by-step explanation:
