4x + 13y = 40
4x + 3y = -40
multiply second equation by -1
4x + 13y = 40
-4x - 3y = 40
add equations together
10y = 80
y = 8
put y in either original equation
4x + 3(8) = -40
4x + 24 = -40
subtract 24 from both sides
4x = 64
x=16
y=8
According to the temperature changes, it is found that:
- On Tuesday, the temperature at Noon was of -28.5 ºF.
- On Wednesday, the temperature at Midnight was of -5.5 ºF.
- On Thursday, the change was of -11.8 ºF.
- On Friday, the temperature at Noon was of -4.5 ºF.
<h3>What is the temperature change?</h3>
- The temperature change during a period is given by the <u>temperature at the end of the period subtracted by the temperature at the start of the period</u>.
On Tuesday:
- At the start of the period, the temperature was of -17.5 ºF.
- The change was of -11 ºF.
Hence:



On Tuesday, the temperature at Noon was of -28.5 ºF.
On Wednesday:
- At the end of the period, the temperature was of 10 ºF.
- The change was of 15.5 ºF.
Hence:


On Wednesday, the temperature at Midnight was of -5.5 ºF.
On Thursday:
- At the end of the period, the temperature was of -24 ºF.
- At the start of the period, the temperature was of -12.2 ºF.
Hence:

On Thursday, the change was of -11.8 ºF.
On Friday:
- At the start of the period, the temperature was of -21.8 ºF.
- The change was of 17.3 ºF.
Hence:



On Friday, the temperature at Noon was of -4.5 ºF.
You can learn more about change at brainly.com/question/24313700
(4,-3) I believe- I got it bc x1 is 3 away from x2 and same with y1 and y2
Answer:
The 95% confidence interval is 
A 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval
Step-by-step explanation:
From the question we are told that
The sample size is 
The mean is 
The standard deviation is 
Given that the confidence level is 95% then the level of significance is mathematically represented as

=> 
=> 
Next we obtain the critical value of
from the normal distribution table , the value is

Generally the margin of error is mathematically represented as

substituting values


The 95% level of confidence interval is mathematically represented as

substituting values


The 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval
Answer:
(1/2), (3/2)
Step-by-step explanation:
midpoint fomula
(x1+x2)/ 2, (y1+y2)/2
(5-4)= 1 1/2 = (1/2)
(-1+4)=3 3/2=(3/2)