All categories

3 years ago

What is the solution to this system of equations?

1 answer:

7 0

<span>
-3x - 3y = 3

y= 7x +15

replace </span>y= 7x +15 into -3x - 3y = 3
-3x - 3(7x+15) = 3
<span>-3x -21x - 45 = 3
-24x = 48
x = 48/-24
x = -2

</span><span>y= 7x +15
</span><span>y= 7(-2) +15
y = -14 + 15
y = 1

solution (-2,1)</span>

You might be interested in

A researcher wants to estimate the percentage of all adults that have used the Internet to seek pre-purchase information in the

Lubov Fominskaja [6]

Answer:

The required sample size for the new study is 801.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

25% of all adults had used the Internet for such a purpose

This means that $\pi = 0.25$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

What is the required sample size for the new study?

This is n for which M = 0.03. So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.03 = 1.96\sqrt{\frac{0.25*0.75)}{n}}$

$0.03\sqrt{n} = 1.96\sqrt{0.25*0.75}$

$\sqrt{n} = \frac{1.96\sqrt{0.25*0.75}}{0.03}$

$(\sqrt{n})^2 = (\frac{1.96\sqrt{0.25*0.75}}{0.03})^2$

$n = 800.3$

Rounding up:

The required sample size for the new study is 801.

4 0

3 years ago

If a game consists of picking a number from a bag of beans numbered 2, 2, 3, 4, and 5 and flipping a coin, which probabilities a

Semenov [28]

The true statement is (d) none of the above

<h3>Missing information</h3>

I. P(3 and tail)

II. P(even and head)

III .P(odd and head)

<h3>How to determine the equivalent probabilities?</h3>

We start by calculating each probability

There is only one 3 in the 5 numbers.

So:

P(3) = 1/5

The probability of a tail in a coin is:

P(Coin) = 1/2

So, we have:

P(3 and tail) = 1/5 * 1/2

P(3 and tail) = 1/10

There are three even numbers in the 5 numbers.

So:

P(even) = 3/5

The probability of a head in a coin is:

P(head) = 1/2

So, we have:

P(even and head) = 3/5 * 1/2

P(even and head) = 3/10

There are two odd numbers in the 5 numbers.

So:

P(odd) = 2/5

The probability of a head in a coin is:

P(head) = 1/2

So, we have:

P(odd and head) = 2/5 * 1/2

P(even and head) = 1/5

By comparing the results, none of the probabilities are equal.

Hence, the true statement is (d) none of the above

Read more about probability at:

brainly.com/question/25870256

#SPJ1

6 0

2 years ago

Is this table proportional? *

galben [10]

Answer:

Step-by-step explanation:

pls give brainlest almost lvled up.

3 0

3 years ago

-4(v + 1) + 6v = 2(v + 2) - 8

Lena [83]

Can someone please help me answer this problem on my profile no one will help me

4 0

3 years ago

Olivia wants to cut 3 3/4 inches from a piece of string.She has already cut off 2 9/16 inches from the piece of string.How much

Roman55 [17]

Answer: she still has to cut off 19/16 inches.

Step-by-step explanation:

Olivia wants to cut 3 3/4 inches from a piece of string. Converting 3 3/4 inches to improper fraction, it becomes 15/4 inches.

She has already cut off 2 9/16 inches from the piece of string. Converting 2 9/16 inches to improper fraction, it becomes 41/16 inches.

Therefore, the length of string that is left for her to cut off would be

15/4 - 41/16 = (60 - 41)/16

= 19/16 inches

6 0

4 years ago