PLEASE HELP! this stuff is.. horrible.

What is the equation of a circle with center (9,-7) and radius 2?

kirza4 [7]

Answer:

B. (x-9)^2 + (y + 7)^2 = 4

Step-by-step explanation:

The standard form of a circle is (x-h)^2 + (y-k)^2 = r^2. Hopefully you can memorize that, because it's very helpful in these problems!

(h,k) is our center, and r is our radius, so plug those values into the standard form:

(x - 9)^2 + (y + 7)2 = 2^2

2^2 = 4, so

B. (x - 9)^2 + (y + 7)2 = 4 is our answer!

3 0

3 years ago

A manufacturing company with 450 employees begins a new product line and must increase their number of employees by 18%. How man

nika2105 [10]

The answer would 531. You would add 18% more employees to the company so the answer is 531. I really hope this helped you. Have a nice day!

4 0

3 years ago

Thickness measurements of ancient prehistoric Native American pot shards discovered in a Hopi village are approximately normally

Dafna1 [17]

Answer:

a) 0.0869 = 8.69% probability that the thickness is less than 3.0 mm

b) 0.0668 = 6.68% probability that the thickness is more than 7.0 mm

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 4.9, \sigma = 1.4$