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
MAXImum [283]
3 years ago
7

Perform the indicated operation and simplify

Mathematics
2 answers:
Alecsey [184]3 years ago
3 0

Answer:

3a

-----

2(a-2)

Step-by-step explanation:

3a+6          a^2 -4

----------- ÷ -----------

8                       4a

Copy dot flip

3a+6          4a

----------- * -----------

8                 a^2 -4

Factor

3(a+2)          4a

----------- * -----------

8                 (a-2) (a+2)

Cancel like terms

3             a

----------- * -----------

2                 (a-2)

3a

-----

2(a-2)

rewona [7]3 years ago
3 0

Answer:

A

Step-by-step explanation:

\frac{3a+6}{8} ÷\frac{a^{2} -4}{4a} = \frac{3(a+2)}{8}*\frac{4a}{(a+2)(a-2)}

take out (a+2) and 4

\frac{3}{2}*\frac{a}{(a-2)}= \frac{3a}{2(a-2)}

You might be interested in
What is the product of (-0.9)(-2.4)?
galina1969 [7]
2.16
Have a great day and good luck! :)
6 0
3 years ago
Read 2 more answers
ANSWER PLS PLS PLS<br><br> Solve the proportion!<br><br> <img src="https://tex.z-dn.net/?f=-%5Cfrac%7B6%7D%7B7%7D%3D%5Cfrac%7Bn%
aliya0001 [1]

To solve this, you need to isolate/get the variable "n" by itself in the equation:

-\frac{6}{7} =\frac{n}{21}    Multiply 21 on both sides to get "n" by itself

(21)(-\frac{6}{7} )=(21)\frac{n}{21}

-\frac{126}{7} =n     Simplify the fraction

-18 = n

8 0
3 years ago
Whats 9 plus 10<br> My calculator broke and i need help
luda_lava [24]

Answer:

19

Step-by-step explanation:

10

+9

10

5 0
3 years ago
If the drama club collected 25,915 points and gave away 71 shirts, how many shirts would be given away when 33,580 points are co
natta225 [31]
<span>25915 (points)/71 (shirts)= 365 (cost per shirt)
</span><span>33580(points)/365(cost per shirt)= 92 shirts total</span>
6 0
3 years ago
Five observations taken for two variables follow.
I am Lyosha [343]

Answer:

a) Figure attached

b) If we see the scatter plot we can conclude that the possible relation between x and y is linear and with a positive correlation since when the values of x increases the values for y increases as well.

c) Cov (X,Y) = \frac{\sum_{i=1}^n (x_i -\bar X)(y_i -\bar Y)}{n-1}

We can find the numerator like this:

\sum_{i=1}^5 (6-16)(6-10)+(11-16)(9-10)+(15-16)(6-10)+(21-16)(17-10)+(27-16)(12-10)=106

And then:

Cov(X,Y) = \frac{106}{5-1}=26.5

d) r=\frac{5(906)-(80)(50)}{\sqrt{[5(1552) -(80)^2][5(586) -(50)^2]}}=0.693  

Step-by-step explanation:

Part a

For this part we use excel in order to create the scatterplot and we got the result on the figure attached.

Part b

If we see the scatter plot we can conclude that the possible relation between x and y is linear and with a positive correlation since when the values of x increases the values for y increases as well.

Part c

The sample covariance is defined as:

Cov (X,Y) = \frac{\sum_{i=1}^n (x_i -\bar X)(y_i -\bar Y)}{n-1}

We can find the numerator like this:

\sum_{i=1}^5 (6-16)(6-10)+(11-16)(9-10)+(15-16)(6-10)+(21-16)(17-10)+(27-16)(12-10)=106

And then:

Cov(X,Y) = \frac{106}{5-1}=26.5

Part d

The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.

And in order to calculate the correlation coefficient we can use this formula:  

r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}  

For our case we have this:

n=5 \sum x = 80, \sum y = 50, \sum xy = 906, \sum x^2 =1552, \sum y^2 =586  

r=\frac{5(906)-(80)(50)}{\sqrt{[5(1552) -(80)^2][5(586) -(50)^2]}}=0.693  

So then the correlation coefficient would be r =0.693

3 0
3 years ago
Other questions:
  • Can someone please help me ASAP!
    14·1 answer
  • What is the value of (gof) (6)?
    8·1 answer
  • What should be the first step to solve this equation 2x+9(x-1)=8(2x+2)-5
    5·2 answers
  • 1. The right section of a prism is in the form of a regular hexagon whose apothem measures 5 cm. If the lateral area is 360cm2,
    7·1 answer
  • Julius sold five times as many computers as Sam sold last year. In total, they sold 78 computers. How many computers did Julius
    7·1 answer
  • Find the approximate surface-area-to-volume ratio of a softball with a radius of 2 inches.
    10·1 answer
  • What is 6×6+12+3×2=???
    15·2 answers
  • Round to the nearest thousands 609​
    5·2 answers
  • Helloppp i need hwlp with this plllss
    10·1 answer
  • Which is the best approximation for the solution of the system of equations? y = a system of equations. y equals negative startf
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!