3/7 - 2<br> ---------- <--fraction/divide<br> 5/14

Solve the system 3x+y=2 5x-y=8

Citrus2011 [14]

Answer:

x= 5/4 ; y= -7/4

Step-by-step explanation:

I will solve your system by substitution.

(You can also solve this system by elimination.)

3x+y=2;5x−y=8

Step: Solve3x+y=2for y:

3x+y+−3x=2+−3x(Add -3x to both sides)

y=−3x+2

Step: Substitute−3x+2foryin5x−y=8:

5x−y=8

5x−(−3x+2)=8

8x−2=8(Simplify both sides of the equation)

8x−2+2=8+2(Add 2 to both sides)

8x=10

8x

8

=

10

8

(Divide both sides by 8)

x=

5

4

Step: Substitute

5

4

forxiny=−3x+2:

y=−3x+2

y=−3(

5

4

)+2

y=

−7

4

(Simplify both sides of the equation)

Answer:

x=

5

4

and y=

−7

4

3 0

3 years ago

A man does not eat for. One week how many hours is that

Artist 52 [7]

Answer:

1 week = 168 hours

Step-by-step explanation:

1 week = 7 days

1 day = 24 hours

1 week * 7 days/ 1 week * 24 hours/1 day = 168 hours

So 1 week = 168 hours

8 0

3 years ago

Read 2 more answers

f the dean wanted to estimate the proportion of all students receiving financial aid to within 3% with 99% reliability, how many

Oksanka [162]

Answer:

n=1849

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".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$z_{\alpha/2}=-2.58, z_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.03$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

Assuming that the proportion is estimated $\hat p =0.5$ . And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.03}{2.58})^2}=1849$

And rounded up we have that n=1849

7 0

3 years ago

Which is congruent or not ABC=DEF <br> ABC=DBC<br> AKR=HKR

Studentka2010 [4]

Xy Uefa the most important things to be a good idea for
It is the first time I have a

As the world to be able to do this

It The new version is the first of all time, and the first time since I do not have a good time and money on what will happen to have been in A