Answer:
C = 8 pi cm
Step-by-step explanation:
The area of a circle is given by
A = pi r^2
16 pi = pi r^2
Divide each side by pi
16 = r^2
Taking the square root
4 = r
The circumference is
C = 2 * pi *r
C = 2* pi *(4)
C = 8 pi cm
Answer:
m<−8
Step-by-step explanation:
Answer:
y=1/2x+2
Step-by-step explanation:
Answer:
300%
Step-by-step explanation:
Given
![y\ \alpha\ \frac{1}{x^2}](https://tex.z-dn.net/?f=y%5C%20%5Calpha%5C%20%5Cfrac%7B1%7D%7Bx%5E2%7D)
Required
Find the percentage change in y when x decreased by 50%
First, convert to equation
![y\ = \ \frac{k}{x^2}](https://tex.z-dn.net/?f=y%5C%20%3D%20%5C%20%5Cfrac%7Bk%7D%7Bx%5E2%7D)
Where k is the constant of proportionality
When x decreased by 50%
![Y = \frac{k}{(x - 0.5x)^2}](https://tex.z-dn.net/?f=Y%20%3D%20%5Cfrac%7Bk%7D%7B%28x%20-%200.5x%29%5E2%7D)
![Y = \frac{k}{(0.5x)^2}](https://tex.z-dn.net/?f=Y%20%3D%20%5Cfrac%7Bk%7D%7B%280.5x%29%5E2%7D)
![Y = \frac{k}{0.25x^2}](https://tex.z-dn.net/?f=Y%20%3D%20%5Cfrac%7Bk%7D%7B0.25x%5E2%7D)
Expand
![Y = \frac{1}{0.25} * \frac{k}{x^2}](https://tex.z-dn.net/?f=Y%20%3D%20%5Cfrac%7B1%7D%7B0.25%7D%20%2A%20%5Cfrac%7Bk%7D%7Bx%5E2%7D)
Substitute
for y
![Y = \frac{1}{0.25} * y](https://tex.z-dn.net/?f=Y%20%3D%20%5Cfrac%7B1%7D%7B0.25%7D%20%2A%20y)
![Y = 4 * y](https://tex.z-dn.net/?f=Y%20%3D%204%20%2A%20y)
![Y = 4 y](https://tex.z-dn.net/?f=Y%20%3D%204%20y)
The percentage change is then calculated as:
![\%Change = \frac{Y - y}{y} * 100\%](https://tex.z-dn.net/?f=%5C%25Change%20%3D%20%5Cfrac%7BY%20-%20y%7D%7By%7D%20%2A%20100%5C%25)
![\%Change = \frac{4y - y}{y} * 100\%](https://tex.z-dn.net/?f=%5C%25Change%20%3D%20%5Cfrac%7B4y%20-%20y%7D%7By%7D%20%2A%20100%5C%25)
![\%Change = \frac{3y}{y} * 100\%](https://tex.z-dn.net/?f=%5C%25Change%20%3D%20%5Cfrac%7B3y%7D%7By%7D%20%2A%20100%5C%25)
![\%Change = 3 * 100\%](https://tex.z-dn.net/?f=%5C%25Change%20%3D%203%20%2A%20100%5C%25)
![\%Change = 300\%](https://tex.z-dn.net/?f=%5C%25Change%20%3D%20300%5C%25)
<em>The percentage in y is 300%</em>
Use point slope form to answer this
Y = x - 10