Let x = your number.
x^2 - 21 = 4x. Subtract 4x from both sides.
x^2 - 4x - 21 = 0. Factor.
(x - 7) (x + 3) = 0. Set each term to 0.
x + 3 = 0. Subtract 3 from both sides.
x = -3. This is the negative solution.
Set the other term equal to zero.
x - 7 = 0. Add 7 to each side.
x = 7. This is the positive solution.
Answer:
Quadrant IV
Step-by-step explanation:
On the graph, the x-axis numbers are positive and the y-axis numbers are negative
So first what we do is we need to get the excluded values. So to get them we have: 8x^4/x^3+7x^4.
Lets factor out the second part. x^3+7x^4 = (x^(3/4)+7x))^4
So then we get 8x^4/(x^(3/4)+7x)^4
8x^4/(x^(3/4)+7x)^4
Using the z-distribution, as we are working with a proportion, it is found that the 99% confidence interval for the proportion of all U. S. Adults who would include the 9/11 attacks on their list of 10 historic events is (0.7458, 0.7942). It means that we are 99% sure that the true proportion for all U.S. adults is between these two bounds.
<h3>What is a confidence interval of proportions?</h3>
A confidence interval of proportions is given by:

In which:
is the sample proportion.
In this problem, the parameters are:

The lower limit of this interval is:

The upper limit of this interval is:

The 99% confidence interval for the proportion of all U. S. Adults who would include the 9/11 attacks on their list of 10 historic events is (0.7458, 0.7942). It means that we are 99% sure that the true proportion for all U.S. adults is between these two bounds.
More can be learned about the z-distribution at brainly.com/question/25890103
Answer:
You'll mark me brainless?! I shouldn't answer corectly then XD
The answer (keep in mind that i'm answering incorrectly) A, or B, or D, or E.
Do you see what I did there ;)
Step-by-step explanation:
May I have brainliest please :)