1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
RSB [31]
3 years ago
6

Find the value of the expression 2x2 - 4x2 + 7x – 7 if x= 3. What is the value if x = 2?

Mathematics
1 answer:
vichka [17]3 years ago
5 0

Answer:

if x= 3, so it's 32  if x= 2, so it's 7

Step-by-step explanation:

You might be interested in
Match the story to the equation: If 1/3 of the drive to Han's school is 2 miles, how long is the whole drive to school? Group of
lubasha [3.4K]

Answer:

2x1/3 sorry if not right

Step-by-step explanation:

5 0
3 years ago
What's the answer to this please help. :)
Alexxandr [17]
I think the answer is 32 if I did my math right sorry if it wrong
6 0
3 years ago
Read 2 more answers
a light switch works 25% of the time, how many times does it not work if switched on 64 times in a week
alexira [117]
25% of 64 is 16
\frac{25}{100}  =  \frac{x}{64}  \\ x =  \frac{64 \times 25}{100}  =  \frac{1600}{100}  = 16
it will work properly 16 times
64 - 16 = 48
it will not work 48 times
hope this helps
7 0
3 years ago
A genetic experiment involving peas yielded one sample of offspring consisting of 420 green peas and 174 yellow peas. Use a 0.01
slavikrds [6]

Answer:

a) z=\frac{0.293 -0.23}{\sqrt{\frac{0.23(1-0.23)}{594}}}=3.649  

b) For this case we need to find a critical value that accumulates \alpha/2 of the area on each tail, we know that \alpha=0.01, so then \alpha/2 =0.005, using the normal standard table or excel we see that:

z_{crit}= \pm 2.58

Since the calculated value is higher than the critical value we have enough evidence to reject the null hypothesis at 1% of significance.

Step-by-step explanation:

Data given and notation

n=420+174=594 represent the random sample taken

X=174 represent the number of yellow peas

\hat p=\frac{174}{594}=0.293 estimated proportion of yellow peas

p_o=0.23 is the value that we want to test

\alpha=0.01 represent the significance level

Confidence=99% or 0.99

z would represent the statistic (variable of interest)

p_v represent the p value (variable of interest)  

Concepts and formulas to use  

We need to conduct a hypothesis in order to test the claim that the true proportion of yellow peas is 0.23:  

Null hypothesis:p=0.23  

Alternative hypothesis:p \neq 0.23  

When we conduct a proportion test we need to use the z statisitc, and the is given by:  

z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}} (1)  

The One-Sample Proportion Test is used to assess whether a population proportion \hat p is significantly different from a hypothesized value p_o.

Calculate the statistic  

Since we have all the info requires we can replace in formula (1) like this:  

z=\frac{0.293 -0.23}{\sqrt{\frac{0.23(1-0.23)}{594}}}=3.649  

Statistical decision  

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.  

The significance level provided \alpha=0.05. The next step would be calculate the p value for this test.  

Since is a bilateral test the p value would be:  

p_v =2*P(z>3.649)=0.00026  

So the p value obtained was a very low value and using the significance level given \alpha=0.05 we have p_v so we can conclude that we have enough evidence to reject the null hypothesis.

b) Critical value

For this case we need to find a critical value that accumulates \alpha/2 of the area on each tail, we know that \alpha=0.01, so then \alpha/2 =0.005, using the normal standard table or excel we see that:

z_{crit}= \pm 2.58

Since the calculated value is higher than the critical value we have enough evidence to reject the null hypothesis at 1% of significance.

5 0
3 years ago
HELP PLEASE! WORTH 30 POINTS! In this diagram, both polygons are regular. What is the value, in degrees, of the sum of the measu
lara [203]

that is the sum of the interior angles of a triangle,or the 3 sided polygons

8 0
3 years ago
Read 2 more answers
Other questions:
  • PRE CALCULUS
    10·1 answer
  • What type of number can be written as a fraction p%q where p and q aré integers and q is not equal to zero
    9·1 answer
  • - Shelia went snowboarding. She spent $118
    14·2 answers
  • Given the equation y=12x, x representing number of hours worked, y representing amount of money earned, how much would John earn
    7·1 answer
  • What fraction equals to 4
    13·2 answers
  • Really confused, can someone help me?
    5·1 answer
  • 7 A. Solid cubical block is 24cm long find its volume​
    9·1 answer
  • Barbara sells iced tea for $1.49 per bottle and water for $1.25 per bottle. She wrote an equation to find the number
    12·1 answer
  • Find the surface area of the prism:
    13·1 answer
  • Write out the sample space for the given experiment. Use the following letters to indicate each choice: M for mushrooms, A for a
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!