All categories

2 years ago

Which ordered pair is a solution to the system of equations?

Mathematics

2 answers:

mixer [17]2 years ago

6 0

(2x - y = -2)2
5x - 2y = -7
4x - 2y = -4
Subtract both
x = -3
5(-3) - 2y = -7
-15 - 2y = -7
-2y = 8, y = -4
Solution: (-3,-4)

Semmy [17]2 years ago

6 0

Answer:

(-3,-4)

Step-by-step explanation:

You might be interested in

Dr. Gilmore gives Lily 17 pills to take. He told her to take one every six hours. In how many days will she take the last pill?

MArishka [77]

5 days because there are 24 hours in a day so every six hours you can take 4 a day

3 0

2 years ago

Solve 11b^2-9=-68 using the square root method

Vladimir79 [104]

Answer:

b=i* $\sqrt{\frac{59}{11} }$ or -i* $\sqrt{\frac{59}{11} }$

Step-by-step explanation:

11b^2-9=-68

11b^2=-59

b^2=-59/11

b=i* $\sqrt{\frac{59}{11} }$ or -i* $\sqrt{\frac{59}{11} }$

"i" in this case is an imaginary number, equal to $\sqrt{-1\\}$

if you haven't learned about these yet, something is wrong with the question

3 0

2 years ago

Which graph shows a negative acceleration?

77julia77 [94]

Answer:

Second Graph.

Explanation:

It's the only graph that is concave down and the slope is decreasing.

4 0

2 years ago

A sample survey is designed to estimate the proportion of sports utility vehicles being driven in the state of California. A ran

mart [117]

Answer:

a) The 95% confidence interval would be given (0.070;0.121).

b) "increase the sample size n"

"decrease za/2 by decreasing the confidence"

Step-by-step explanation:

Notation and definitions

$X=48$ number of vehicles classified as sports utility.

$n=500$ random sample taken

$\hat p=\frac{48}{500}=0.096$ estimated proportion of vehicles classified as sports utility vehicles.

$p$ true population proportion of vehicles classified as sports utility vehicles.

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

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

(a) Use a 95% confidence interval to estimate the proportion of sports utility vehicles in California. (Round your answers to three decimal places.)

The confidence interval would be given by this formula :

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

For the 95% confidence interval the value of $\alpha=1-0.5=0.05$ and $\alpha/2=0.025$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=1.96$

And replacing into the confidence interval formula we got:

$0.096 - 1.96 \sqrt{\frac{0.096(1-0.096)}{500}}=0.070$

$0.096 + 1.96 \sqrt{\frac{0.096(1-0.096)}{500}}=0.121$

And the 95% confidence interval would be given (0.070;0.121).

We are confident (95%) that about 7.0% to 12.1% of vehicles in California are classified as sports utility .

(b) How can you estimate the proportion of sports utility vehicles in California with a higher degree of accuracy? (HINT: There are two answers. Select all that apply.)

For this case we just have two ways to increase the accuracy one is "increase the sample size n" since if we have a larger sample size the estimation would be more accurate. And the other possibility is "decrease za/2 by decreasing the confidence" because if we decrease the confidence level the interval would be narrower and accurate

7 0

2 years ago

Yukarıda verilen şekilde,

olga2289 [7]

C, 60 hope this helps it helped me on my test

6 0

2 years ago