Determine the equation for the line of best fit to represent the data.

Which ordered pair is a solution of the equation? y=8x+3y=8x+3

Mrac [35]

Multiply the first equation by 4 (so that both equations will have 8x terms) and then subtract:

8x-20y = -24

8x +3y = 68

------------

0 -23y = -92

Now divide both sides by -23:

y = 4

Find x by plugging y=4 into either equation:

8x +3(4) = 68

8x = 68 - 12

8x = 56

x = 7

So the answer is ordered pair is (7,4)

3 0

3 years ago

Read 2 more answers

Twin brothers, person a and person b, can mow their grandparent's lawn together in 18 minutes. person a could mow the lawn by

Alex777 [14]

What are the answer choices

5 0

3 years ago

Suppose that you are in charge of evaluating teacher performance at a large elementary school. One tool you have for this evalua

Strike441 [17]

Answer:

a) Standard error = 2

b) Range = (76.08, 83.92)

c) P=0.69

d) Smaller

e) Greater

Step-by-step explanation:

a) When we have a sample taken out of the population, the standard error of the mean is calculated as:

$\sigma_m=\dfrac{\sigma}{\sqrt{n}}=\dfrac{10}{\sqrt{25}}=\dfrac{10}{5}=2$

where n is te sample size (n=25) and σ is the population standard deviation (σ=10).

Then, the standard error of the classroom average score is 2.

b) The calculations for this range are the same that for the confidence interval, with the difference that we know the population mean.

The population standard deviation is know and is σ=10.

The population mean is M=80.

The sample size is N=25.

The standard error of the mean is σM=2.

The z-value for a 95% confidence interval is z=1.96.

The margin of error (MOE) can be calculated as:

$MOE=z\cdot \sigma_M=1.96 \cdot 2=3.92$

Then, the lower and upper bounds of the confidence interval are:

$LL=M-t \cdot s_M = 80-3.92=76.08\\\\UL=M+t \cdot s_M = 80+3.92=83.92$

The range that we expect the average classroom test score to fall 95% of the time is (76.08, 83.92).

c) We can calculate this by calculating the z-score of X=79.

$z=\dfrac{X-\mu}{\sigma}=\dfrac{79-80}{2}=\dfrac{-1}{2}=-0.5$

Then, the probability of getting a average score of 79 or higher is:

$P(X>79)=P(z>-0.5)=0.69146$

The approximate probability that a classroom will have an average test score of 79 or higher is 0.69.

d) If the sample is smaller, the standard error is bigger (as the square root of the sample size is in the denominator), so the spread of the probability distribution is more. This results then in a smaller probability for any range.

e) If the population standard deviation is smaller, the standard error for the sample (the classroom) become smaller too. This means that the values are more concentrated around the mean (less spread). This results in a higher probability for every range that include the mean.

6 0

3 years ago

How do you determine the value of isosceles triangles?

amid [387]

There's really no such thing as the value of a triangle.

Every triangle has three sides, three angles, a base, a height, and an area,
and there could be problems that ask us to find any one of those.

Whatever we need to find, the process is always the same:

-- Take the information that's given.

-- Gather up everything you can remember that talks about a relationship
between what you're given and what you need to find.

-- Use them together to find the missing value.

6 0

2 years ago

BRAINLIESTT ASAP! PLEASE HELP ME :)<br> thanks!

nadya68 [22]

Answer:

B

Step-by-step explanation:

Please see the answer in the picture attached below.

" From Step 1: We find that Angle N1 equals to 75 gradius => Answers A and C wrong. Answers B and D are left.

" From Step 4: We find that Angle N2 equals to 129 gradius => Answer B is true.

You don't need to find the exact value of the angle N3 in oder to choose the right answers from A,B,C,D.

Hope this answer can help you. Have a nice day!

7 0

3 years ago