-9 ≤ x ≤ 4
it is less than or equal to -9°F, but also less than 4°F
Hope this helps
Answer:
8 ft
Step-by-step explanation:
the ladder will make a right angle triangle with the house. The hypotenuse of the triangle is the ladder, 20 ft, and the height of the triagnle is 18 ft.
Solve for the base of the right angle triangle using pythagorean's theorem:
c=20, a=18, b=?



round to the nearest foot,
b = 8 ft
The correlation coefficient of the health research institute data measures the relationship between the age and the years of the smokers
The correlation coefficient is 0.53
<h3>How to calculate the correlation coefficient</h3>
The correlation coefficient (r) is calculated as:
![r = \frac{n(\sum xy) - \sum x \sum y}{\sqrt{[n \sum x^2 - (\sum x)^2][n\sum y^2 - (\sum y)^2}}](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7Bn%28%5Csum%20xy%29%20-%20%5Csum%20x%20%5Csum%20y%7D%7B%5Csqrt%7B%5Bn%20%5Csum%20x%5E2%20-%20%28%5Csum%20x%29%5E2%5D%5Bn%5Csum%20y%5E2%20-%20%28%5Csum%20y%29%5E2%7D%7D)
Using the given parameters, we have:
![r = \frac{20 *8249 - 1257* 116}{\sqrt{[20 * 98823 - 1257^2][20 * 836 - 116^2}}](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7B20%20%2A8249%20-%201257%2A%20116%7D%7B%5Csqrt%7B%5B20%20%2A%2098823%20-%201257%5E2%5D%5B20%20%2A%20836%20-%20116%5E2%7D%7D)
Evaluate the exponents
![r = \frac{20 *8249 - 1257* 116}{\sqrt{[20 * 98823 - 1580049][20 * 836 - 13456}}](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7B20%20%2A8249%20-%201257%2A%20116%7D%7B%5Csqrt%7B%5B20%20%2A%2098823%20-%201580049%5D%5B20%20%2A%20836%20-%2013456%7D%7D)
Evaluate the products
![r = \frac{164980 - 145812}{\sqrt{[1976460 - 1580049][16720 - 13456}}](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7B164980%20-%20145812%7D%7B%5Csqrt%7B%5B1976460%20-%201580049%5D%5B16720%20-%2013456%7D%7D)
Evaluate the differences

Evaluate the product

Evaluate the root

Evaluate the quotient

Hence, the correlation coefficient is 0.53
Read more about correlation coefficient at:
brainly.com/question/1564293
Answer:
25
Step-by-step explanation: