Respuesta :
Answer:
These tables represent a quadratic function with a vertex at (0,3). What is the
average rate of change for the interval from x = 8 to x = 9?
Interval
х
0
1
2
3
4
5
ilm
у
3
2
-1
-6
-13
-22
--33
0 to 1
1 to 2
2 to 3
3 to 4
4 to 5
5 to 6
Average rate
of change
-1
3-2
-3
1-2
-5
1-2
-7
1-2
-9
1-2
-11
6
O A. -78
O B. -61
C.-2
O D. -17
The average rate of change on the given interval is -17, so the correct option is D.
How to get the average rate of change?
For a function f(x), the average rate of change on an interval (a, b) is given by:
[tex]r = \frac{f(b) - f(a)}{b - a}[/tex]
Here we have the table:
x y
0 3
1 2
2 -1
3 -6
4 -13
5 -22
Using that data we can find the equation of the parabola.
Because of the first point, we know that:
y = a*x^2 + b*x + 3
Using the second and third pairs, we can write:
2 = a + b + 3
-1 = a*2^2 + b*2 + 3
Then we can solve this sytem of equations, if we simplify the equations we get:
a + b = -1
4a + 2b = -4
To solve this, we need to isolate one of the variables, I will isolate a on the first equation:
a = -1 - b
Then we can replace this with the other equation:
4*(-1 - b) + 2b = -4
Now we can solve this for b.
-4 - 4b + 2b = -4
-2b = 0
b = 0
Then:
a = -1 - b = -1 - 0 = -1
Then the quadratic equation is:
y = f(x) = -x^2 + 3
Now, we need to get:
f(8) = -(8)^2 + 3 = -61
f(9) = -(9)^2 + 3 = -78
Then the average rate of change is:
[tex]r = \frac{-78 - (-61)}{9 - 8} = -17[/tex]
So the correct option is D.
If you want to learn more about rates of change, you can read:
https://brainly.com/question/8728504
