A NONA=9, nonagon has 9 sides, so it's perimeter is 7+7+7+7+7+7+7+7+7, or 63, and we know the apothem.
bearing in mind that the area of a regular polygon is
(1/2)ap a = apothem, p = perimeter
so in this case that'd be (1/2)(5)(63).
Answer:
16a +32b - 8c
Step-by-step explanation:
8(2a + 4b - c)
Distribute
8*2a + 8*4b+ 8*(-c)
16a +32b - 8c
Answer:
Step-by-step explanation:
You divide the price with 9.25.
For example, if I wanted to buy a pouch(3.00) and pens(4.59), and the total without tax was 7.59 (add the prices), the tax would be 0.70 because 7.59/9.25=0.70. If I add 0.70 to 7.59, I would have to pay 8.29.
Hope this helps!
Answer:
The sample size needed if the margin of error of the confidence interval is to be about 0.04 is 18.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
![\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=%5Cpi%20%5Cpm%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
In which
z is the zscore that has a pvalue of
.
The margin of error is:
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Past studies suggest this proportion will be about 0.15
This means that ![p = 0.15](https://tex.z-dn.net/?f=p%20%3D%200.15)
Find the sample size needed if the margin of error of the confidence interval is to be about 0.04
This is n when M = 0.04. So
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
![0.04 = 1.96\sqrt{\frac{0.15*0.85}{n}}](https://tex.z-dn.net/?f=0.04%20%3D%201.96%5Csqrt%7B%5Cfrac%7B0.15%2A0.85%7D%7Bn%7D%7D)
![0.04\sqrt{n} = 1.96\sqrt{0.15*0.85}](https://tex.z-dn.net/?f=0.04%5Csqrt%7Bn%7D%20%3D%201.96%5Csqrt%7B0.15%2A0.85%7D)
![\sqrt{n} = \frac{1.96\sqrt{0.15*0.85}}{0.04}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.96%5Csqrt%7B0.15%2A0.85%7D%7D%7B0.04%7D)
![(\sqrt{n})^{2} = (\frac{1.96\sqrt{0.15*0.85}}{0.04})^{2}](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E%7B2%7D%20%3D%20%28%5Cfrac%7B1.96%5Csqrt%7B0.15%2A0.85%7D%7D%7B0.04%7D%29%5E%7B2%7D)
![n = 17.5](https://tex.z-dn.net/?f=n%20%3D%2017.5)
Rounding up
The sample size needed if the margin of error of the confidence interval is to be about 0.04 is 18.
Answer:
The inverse function is g(x) = ±
, x ≥ -12 ⇒ D
Step-by-step explanation:
* Lets explain how to find the inverse function
- The steps of find the inverse of function f(x)
# Write y = f(x)
# Switch x and y
# Solve to find the new y
* Lets solve the problem
∵ f(x) = 9x² - 12
- Do the steps above
- Put y = f(x)
∵ y = f(x)
∴ y = 9x² - 12
- Switch x and y
∴ x = 9y² - 12
- Add both sides by 12
∴ x + 12 = 9y²
- take √ for both side don't forget to put ± in-front of it
∴ ±
= 3y
- Divide both sides by 3
∴ y = ± ![\frac{\sqrt{x+12}}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csqrt%7Bx%2B12%7D%7D%7B3%7D)
∵ There is no square root for negative number
∴ x + 12 ≥ 0 ⇒ subtract 12 from both sides
∴ x ≥ -12
- The function is defined for all values of x greater than or equal -12
∴ The inverse function is g(x) = ±
, x ≥ -12