If we put the parabola in a coordinate system with vertex at the origin and facing the positive x axis. We have the following points lying on the curve:
(4, 8), (4, -8)
For parabola facing right:
y2 = 4ax
Substituting either coordinates to solve for a:
a = 4
Therefore, the microphone should be placed 4 inches from the bottom of the disk.
Answer: 7
Step-by-step explanation:
i think it right could be wrong tho
Answer:
EF = 9
GF = 2
Step-by-step explanation:
For EF, we want to find the distance between their c coordinates, since their y coordinates are the same. We want the distance between -4 and 5, which when you add their distance from 0, is 9.
For GF, they share the same x coordinate, so you're finding the distance between their y coordinates, which are 3 and 5. The distance between the two is 2, so the length of GF is 2.
Answer:
B. y = -0.58x^2 -0.43x +15.75
Step-by-step explanation:
The data has a shape roughly that of a parabola opening downward. So, you'll be looking for a 2nd-degree equation with a negative coefficient of x^2. There is only one of those, and its y-intercept (15.75) is in about the right place.
The second choice is appropriate.
_____
The other choices are ...
A. a parabola opening upward
C. an exponential function decaying toward zero on the right and tending toward infinity on the left
D. a line with negative slope (This might be a good linear regression model, but the 2nd-degree model is a better fit.)