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3 years ago

Solve this system of equations using the substitution method.

Mathematics

1 answer:

miskamm [114]3 years ago

6 0

Answer:

(5,14)

Step-by-step explanation:

4x-6=2x+4 because I chose any of the y values

change of subjects ⬇️

4x-2x =4+6

2x=10

2x÷2 and 10÷2

⬆️ making x stand alone

x= 5

put x into any of the equation

y=2(5)+4

y= 10+4

y=14

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If your earned income for 2021 will be $84,686, Calculate what you will pay

Svetach [21]

Answer:

5250.53 social security, 1227.95 Medicare

Step-by-step explanation:

84686x.062=5250.53 in social security

84686x.0145=1227.95 in Medicare

7 0

3 years ago

1) 3n-4 = -13<br> Solve & show work

Taya2010 [7]

Answer:

-3

Step-by-step explanation:

3n-4=-13

+4 +4

3n =-9

3 3

I hope that helped

5 0

3 years ago

If C= (-10, -9, -8, -7 ,-6 , -5) and D= ( -6, -5, -4, -3, -2, -1, ) , what is C n D ?

andrey2020 [161]

Answer:

C ∩ D = -5, -6

Step-by-step explanation:

Commons ones in both C and D are -5 and -6

7 0

3 years ago

Flow meters are installed in urban sewer systems to measure the flows through the pipes. In dry weatherconditions (no rain) the

ziro4ka [17]

Answer:

a) $\frac{(8)(30.23)^2}{20.09} \leq \sigma^2 \leq \frac{(8)(30.23)^2}{1.65}$

$363.90 \leq \sigma^2 \leq 4430.80$

Now we just take square root on both sides of the interval and we got:

$19.08 \leq \sigma \leq 66.56$

b) For this case we are 98% confidence that the true deviation for the population of interest is between 19.08 and 66.56

Step-by-step explanation:

423.6, 487.3, 453.2, 402.9, 483.0, 477.7, 442.3, 418.4, 459.0

Part a

The confidence interval for the population variance is given by the following formula:

$\frac{(n-1)s^2}{\chi^2_{\alpha/2}} \leq \sigma^2 \leq \frac{(n-1)s^2}{\chi^2_{1-\alpha/2}}$

On this case we need to find the sample standard deviation with the following formula:

$s=sqrt{\frac{\sum_{i=1}^8 (x_i -\bar x)^2}{n-1}}
And in order to find the sample mean we just need to use this formula:
[tex]\bar x =\frac{\sum_{i=1}^n x_i}{n}$

The sample deviation for this case is s=30.23

The next step would be calculate the critical values. First we need to calculate the degrees of freedom given by:

$df=n-1=9-1=8$

The Confidence interval is 0.98 or 98%, the value of $\alpha=0.02$ and $\alpha/2 =0.01$ , and the critical values are:

$\chi^2_{\alpha/2}=20.09$

$\chi^2_{1- \alpha/2}=1.65$

And replacing into the formula for the interval we got:

$\frac{(8)(30.23)^2}{20.09} \leq \sigma^2 \leq \frac{(8)(30.23)^2}{1.65}$

$363.90 \leq \sigma^2 \leq 4430.80$

Now we just take square root on both sides of the interval and we got:

$19.08 \leq \sigma \leq 66.56$

Part b

For this case we are 98% confidence that the true deviation for the population of interest is between 19.08 and 66.56

4 0

4 years ago

A grocery store owner budgets $5,000 to buy and maintain a booth for 300 days to give out samples of food. If she bought the boo

serious [3.7K]

Answer:

x ≤ $12 a day

Step-by-step explanation:

5000-1400=3600

3600/300=12

7 0

3 years ago