pls HELPPP !

solve the systems of equations of x+2y=21 and -2x-y=-12

I will do 9 only. You can do 11.

Question 9

sin(60) = x/8

sin(60)(8) = x

4•sqrt{3} = x

x^2 + y^2 = 8^2

(4•sqrt{3})^2 + y^2 = 64

16(3) + y^2 = 64

48 + y^2 = 64

y^2 = 64 - 48

y^2 = 16

sqrt{y^2} = sqrt{16}

y = 4

Do 11 the same way.

Answer:

no

Step-by-step explanation:

Hello There!

We can figure out if the given side lengths form a right triangle using the Pythagorean Theorem

The Pythagorean Theorem states that the hypotenuse (longest side) squared equal to sum of the two legs squared

so if it is a right triangle then

[tex]74^2=71^+24^2[/tex]

[tex]74^2=5476\\71^2=5041\\24^2=576\\5041+576=5617\\5476\neq 5617[/tex]

5617 is not equal to 5476 therefore the given side lengths do not form a right triangle

~TheMathWIz

Answer: Rock Silence? I dont know  Rock No Music?

Step-by-step explanation:

Answer:

pure dead silence

Step-by-step explanation:

Answer:

second option.

Step-by-step explanation:

mark me as brainliest plz

Answer:

Yes it's a positive linear graph

Step-by-step explanation:

Answer:

yes dear it's a positive linear graph.

Answer:

a) 0.0228 = 2.28% probability of a northward displacement of less than 500 kilometers

b) 0.0808 = 8.08% probability of a northward displacement of less than 500 kilometers

c) 1200 kilometers, because in this case, the will be a higher probability of a northward displacement that is less than 500 kilometers.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Standard deviation of 500 kilometers

This means that [tex]\sigma = 500[/tex]

a. Assuming the mean is 1500 kilometers, what is the probability of a northward displacement of less than 500 kilometers?

Mean of 1500 km means that [tex]\mu = 500[/tex]

The probability is the pvalue of Z when X = 500. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{500 - 1500}{500}[/tex]

[tex]Z = -2[/tex]

[tex]Z = -2[/tex] has a pvalue of 0.0228

0.0228 = 2.28% probability of a northward displacement of less than 500 kilometers.

b. Assuming the mean is 1200 kilometers, what is the probability of a northward displacement of less than 500 kilometers?

Now [tex]\mu = 1200[/tex]

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{500 - 1200}{500}[/tex]

[tex]Z = -1.4[/tex]

[tex]Z = -1.4[/tex] has a pvalue of 0.0808

0.0808 = 8.08% probability of a northward displacement of less than 500 kilometers.

c. If, in fact, the northward displacement is less than 500 kilometers, which is the more plausible mean, 1200 or 1500 kilometers?

1200 kilometers, because in this case, the will be a higher probability of a northward displacement that is less than 500 kilometers.

Answer:

the cost of each is  £10 and  £8 respectively

Step-by-step explanation:

Let us assume the cost of per DVD be x

And the cost of per CD be y

Now as per the question

The following equations should be made

3x + 4y = £62.00

4x + 3y = £64.00

Now multiply by 4 in equation 1 and 3 in equation 2

12x + 16y = £248

12x + 9y = £192

7y =  £56

y =  £8

Now put the value of y in any of the above equation

3x + 4( £8) =  £62

3x +  £32 =  £62

3x = 30

x =  £10

Hence, the cost of each is  £10 and  £8 respectively

Answer:

Part A:

I would multiply the length, width, and depth of the pool to find the volume of it. That would be how much water can fit inside. 25 ft x 15 ft x 10 ft = 3750 ft

Part B:

a. 3750 ft

Answer:

40%

Step-by-step explanation:

Because there are 5 rectangle total, we can dive 100% into 5 parts.

Each part is then 20%, there are 2 shaded rectangles thus the answer is 40%.

Answer:

36

Step-by-step explanation:

Answer:

No. It is not. The opposite is -5

Step-by-step explanation:

I -5 I

The symbols; | | represents absolute value.

It gives the non negative value of that number irrespective of the sign of the number.

That is;

| -a | = a and | a | = a

So in this case;

| -5 | = 5

Opposite of 5 = -5

So the answer is FALSE!

Answer:

Step-by-step explanation:

25

Answer:

Step-by-step explanation:

It is easy to see that (-2, 0) and (0, -4) are points on the line.

gradient = (difference of y-coordinates)/(difference of x-coordinates) = (0-(-4))/(-2-0) = 4/(-2) =  -2

Answer:

b

Step-by-step explanation:

Answer:

<B=24

Step-by-step explanation:

<B=x

<A=5(x+7.2)

x+5(x+7.2)=180

x+5x+36=180

6x=180-36

6x=144

x=24

Answer and Step-by-step explanation:

When two angles are supplementary, the add up to 180 degrees.

Measure of angle A is 5 times the sum of the measure of angle B + 7.2.

So, we have b, and we have a.

a + b = 180

a = 5(b + 7.2)

b = ?

We input 5(b + 7.2) for a into the equation.

5(b + 7.2) + b = 180

Now we distribute the 5 and combine like terms.

5b + 36 + b = 180

6b + 36 = 180

Subtract 36 from both sides, then divide both sides by 6 to get b.

6b = 144

b = 24

The measure of angle B is 24 degrees.

#teamtrees #PAW (Plant And Water)

Answer:

a) The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

b) The margin of error is of 0.03.

Step-by-step explanation:

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

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].

Point estimate:

The point estimate is [tex]\pi[/tex].

Margin of error:

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

(a) What is the point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future.

579 out of 1007 adults. So

[tex]\pi = \frac{579}{1007} = 0.575[/tex]

Rounding to two decimal places, 0.58

The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

(b) At 90% confidence, what is the margin of error

90% confidence level

So [tex]\alpha = 0.1[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]M = 1.645\sqrt{\frac{0.58*0.42}{1007}}[/tex]

[tex]M = 0.03[/tex]

The margin of error is of 0.03.

Answer:

Step-by-step explanation:

because in square all sides are equal

Answer:

bc=28

Step-by-step explanation:

give them brainliest

Answer:

We accept the null hypothesis, that is, that the population mean is not different from 0.7.

Step-by-step explanation:

A brochure claims that the average maximum height a certain type of plant is 0.7 m.

This means that the null hypothesis is:

[tex]H_{0}: \mu = 0.7[/tex]

A gardener suspects that this estimate is not accurate locally due to soil conditions.

Hypothesis test to determine whether the population mean is different from 0.7m, which means that the alternate hypothesis is:

[tex]H_{a}: \mu \neq 0.7[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

0.7 is tested at the null hypothesis:

This means that [tex]\mu = 0.7[/tex]

A random sample of 43 plants is taken. The mean height of the plants in the sample is 0.65m.

This means, respectively, that [tex]n = 43, X = 0.65[/tex]

Assume that the population standard deviation is 0.2 m.

This means that [tex]\sigma = 0.2[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.65 - 0.7}{\frac{0.2}{\sqrt{43}}}[/tex]

[tex]z = -1.64[/tex]

Pvalue of the test:

Since we are testing that the mean is different of a value, and z is negative, the pvalue of the test is 2 multiplied by the pvalue of z = -1.64

z = -1.64 has a pvalue of 0.0505

2*0.0505 = 0.101

Using a 1% level of significance, perform a hypothesis test to determine whether the population mean is different from 0.7m.

0.101 > 0.01, which means that we accept the null hypothesis, that is, that the population mean is not different from 0.7.

Answer:

2/8 is the median

Step-by-step explanation:

Answer: The median is 2/8

Step-by-step explanation:

Because the median is the middle number, and 2/8 is at the middle.

Answer:

5/6

Step-by-step explanation:

Because there are 6 sides, and it's saying we need a greater number than 1. And there are 5 other numbers.

Answer:

A,C,D,F

Step-by-step explanation:

Answer:

Open circle going right. <-- graphed

Step-by-step explanation:

1billion is the correct answerStep-by-step explanation: