I don't understand this quadratic functions question please help.

Is this right???<br><br> I give Brainliest !

ratelena [41]

Answer:

It is right

Step-by-step explanation:

good job whatever your name is! you are very smart

5 0

3 years ago

PLEASE HELP!! Will mark brainlest!!

vlada-n [284]

Answer:

I'm not even lying, it's none of them ;-;

btw if you want, can you give me brainliest :((

7 0

3 years ago

Read 2 more answers

A cube has a side length of 4 feet what is the volume of the cube

dalvyx [7]

Answer:

V=64

Step-by-step explanation:

What you do is go based off the volume formula of a cube which is V=a^3.

You have a side length of 4.

V=4^3.

V=64.

6 0

3 years ago

Rewrite −1 + 2i in polar form.

raketka [301]

The length of the radius would sqrt(1+4), or sqrt(5).
2
The angle would be in Quadrant II and would be arctan ------ , or arctan (-2).
-1

Find this angle using a calculator or table.

Then you end up with -1+2i = sqrt(5) angle arctan(-2). The angle would be + and measured from the + horizontal axis.

8 0

3 years ago

An article presents measures of penetration resistance for a certain fine-grained soil. Fifteen measurements, expressed as a mul

balu736 [363]

Answer:

$2.64-2.14\frac{1.32}{\sqrt{15}}=1.911$

$2.64+2.14\frac{1.32}{\sqrt{15}}=3.369$

So on this case the 95% confidence interval would be given by (1.911;3.37)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=2.64$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=1.32 represent the sample standard deviation

n=15 represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=15-1=14$

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.05$ and $\alpha/2 =0.025$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,14)".And we see that $t_{\alpha/2}=2.14$

Now we have everything in order to replace into formula (1):

$2.64-2.14\frac{1.32}{\sqrt{15}}=1.911$

$2.64+2.14\frac{1.32}{\sqrt{15}}=3.369$

So on this case the 95% confidence interval would be given by (1.911;3.37)

6 0

4 years ago