There are 220 students in the seventh grade, and 20% are in the Environmental Club. How many students are in the Environmental Club?

The correct option is (D). The given system of equations has only 2 solutions, which are (−3, 1) and (−13/4, −3/4).

The given system of equations is:x − y = −4 ...(1)y = √(2x + 3) − 2 ...(2)

Squaring on both sides of equation (2), we get:(y + 2)² = 2x + 3y² + 4y + 4 = 2x + 7y² − 2x = −4y² + 4y + 3 ...(3)

Substituting the value of x from equation (1) into equation (3), we get:−4y² + 4y + 3 = 0

Multiplying through by −1, we get:4y² − 4y − 3 = 0

On solving the above quadratic equation, we get:y = [4 ± √(16 + 48)]/8y = [4 ± √64]/8y = [4 ± 8]/8y = 1 or y = −3/4

Substituting the value of y in equation (1), we get:When y = 1, x − 1 = −4x = −4 + 1x = −3

When y = −3/4, x − [−3/4] = −4x = −4 − [−3/4]x = −13/4

Therefore, the given system of equations has only 2 solutions, which are (−3, 1) and (−13/4, −3/4).

Hence, the correct option is (D) 2.

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Answer:

X = 25, Angles are 65 degrees

Step-by-step explanation:

3x-10 = x+40

2x=50

x=25

Yes, it would be a scalene triangle. This can happen.

The Triangle sides have to be greater than c.

a+b > c

With the given inches, substitute it into the equations:

a = 3 in

b = 5 in

c = 9 in

3 + 5 > 9

Solve.

9 > 9

This is False since because a + b is not > c. a + b is equal to c.

ANSWER

EXPLANATION

The Chairman and Co-Chairman are specific positions, so order matters. We first select the chairman out of 10 people and then, the Co-Chairman out of the 9 people left,

The statement that proves that polygon ABCD is not a rectangle is: C. Slope of AD × slope of AB ≠ -1 and slope of BC × slope of AB ≠ -1.

A rectangle is a quadrilateral that has four right angles, this means that two sides of the rectangle intersect each other perpendicularly to form right angles.

Thus, the slope of each pair of sides that intersect perpendicularly equals -1.

Therefore, for polygon ABCD to be a rectangle, we must prove that each pair of intersecting sides that meet have a a slopes that gives -1 when multiplied together. If the product of their slopes is not equal to -1, then the polygon is not a rectangle.

Conclusively, the statement that proves that polygon ABCD is not a rectangle is: C. Slope of AD × slope of AB ≠ -1 and slope of BC × slope of AB ≠ -1.

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When calculating a chi-square, the observed frequencies are based on the information from our sample data.

When calculating a chi-square, the observed frequencies are based on the information from our sample data. The observed frequency (f_obs) is the frequency that a certain event or category actually appears in our data.

We use observed frequencies to test if there is any significant difference between the observed and expected frequencies.

Chi-square is a test used to examine the association between two variables. It compares the observed frequencies to the expected frequencies to test the null hypothesis that there is no association between the variables.

The formula for calculating chi-square is:χ2=Σ(f_obs−f_exp)2f_exp , where χ2 is the chi-square statistic, f_obs is the observed frequency, f_exp is the expected frequency, and Σ is the sum of all categories or events.

The chi-square test is used in many fields, including biology, psychology, sociology, and marketing. The test helps to determine if two categorical variables are independent or not.

The chi-square test can also be used to compare observed frequencies to expected frequencies in a contingency table. It can be used to determine if there is a significant difference between the expected and observed frequencies.

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Answer:15

Step-by-step explanation:

In a square each side is the same length so you simply take 60 and divide it by 4 and you get 15.

Answer:

A. Sample space = 6

B. 0.17

C. No

D. Yes

Step-by-step explanation:

A. The sample space of an experiment is the set of all possible outcomes of that experiment.

since there are three colours and 2 outcomes for a coin toss,

sample space = 3 * 2 = 6

B. Probability of picking a green first = 4/12 = 1/3

probability of a tail = 1/2

Probability of a green and a tail, P(A) = 1/3 * 1/2 = 0.17

C. No.

Considering the two events;

A; green card is picked first

C ; a green or red card is picked

There is an intersection point for the two events.  Therefore, they are not mutually exclusive.

D. Yes.

Considering the two events;

A; green card is picked first

B ; a blue or red card is picked

There is no intersection point for the two events. Therefore, they are mutually exclusive.

Answer:

\(\frac{7}{2}\)

Step-by-step explanation:

Given a quadratic equation in standard form

ax² + bx + c = 0 ( a ≠ 0 ), then

the product of the roots = \(\frac{c}{a}\)

2x² + 4x + 7 = 0 ← is in standard form

with a = 2, c = 7 , thus

product of roots = \(\frac{7}{2}\)

Answer:

x=\(\frac{-2±\sqrt[i]{10} }{2}\)

Step-by-step explanation:

pls ignore the "A" after -2! i hope this helps <3

The possible numbers of ponds at the hatchery are 1, 2, 3, 5, 6, 10, 15, 30, 22,491, 44,982, 67,473, 112,455, 134,946, 224,910, 337,365, and 674,730.

To determine the number of possible ponds at the hatchery, we need to find the factors of 674,730. By finding the factors, we can determine the possible ways the fish can be divided evenly among the ponds. Here are the factors of 674,730:

1, 2, 3, 5, 6, 10, 15, 30, 22491, 44982, 67473, 112455, 134946, 224910, 337365, 674730

Therefore, the possible numbers of ponds at the hatchery are 1, 2, 3, 5, 6, 10, 15, 30, 22,491, 44,982, 67,473, 112,455, 134,946, 224,910, 337,365, and 674,730.

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Answer:

umm im not smart sorry

Step-by-step explanation:

Answer:

One half of 3/4 teaspoon is equal to 3/8 or 0.375 teaspoons. One method of finding the answer in the fraction form of 3/8 is to multiply the fraction 1/2 by 3/4 : )

Step-by-step explanation:

One half of 3/4 teaspoon is equal to 3/8 or 0.375 teaspoons.

Here, we have,

given that,

what is half of 3/4 teaspoon

One method of finding the answer in the fraction form of 3/8 is

to multiply the fraction 1/2 by 3/4 ,

or, we can divide 3/4 by 2

i.e. 1/2 × 3/4

as, half = 1/2

so, we get,

=> 3/ 2×4

=> 3/8

=>0.375

Hence, One half of 3/4 teaspoon is equal to 3/8 or 0.375 teaspoons.

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Answer:

$28.68

Step-by-step explanation:

Answer:

Xavier will have $23.68 left.

Step-by-step explanation:

50- 26.32=23.68

Answer:

with what?

Step-by-step explanation:

Answer:

the thrird option

Step-by-step explanation:

Answer:

21

Step-by-step explanation:

a=( (a+b)/2 ) * h

A= 5+9/2 * 3

Answer:

9 + 5 = 14 x 3 = 42 divided by 2 is 21

Answer:

9/11

Step-by-step explanation:

6467 ytgychuuht6ctctcrxrctfctcyg

Answer:

\(47.25\\)

Step-by-step explanation:

\(42 \times 1.125\)

\(=47.25\)

Answer:

$25.2

Step-by-step explanation:

Answer:

$6.25

Step-by-step explanation:

10 pencils = $0.5 times 10 = $5

$5 plus $1.25 (price of the notebook) = $6.25

Answer: B. x=10

Step-by-step explanation:

Concept

- If it is an isosceles triangle, then the altitude would also be the median of the base, meaning that it divides the base evenly.

- We are going to use the Pythagorean theorem which is a²+b²=c², where [a] and [b] are legs, and [c] is the hypotenuse.

Given

Hypotenuse (relative) = √74

Altitude (one leg) = 7

The other leg (half of the base) = x/2

Solve

a² + b² = c²

(7)² + (x/2)² = (√74)²

49 + x²/4 = 74

x²/4 = 25

x² = 100

x = 10

Hope this helps!! :)

Please let me know if you have any questions

Answer:

A=B+H

Step-by-step explanation:

I rearange the letters and also I put a plus singe

Given:

Nuts = $2.50

Cereal mixture = $1

Find -: How much each should be added.

Sol:

Obtain = 60 kg.

Let nuts = x kg

Cereal = y kg

To obtain 60 kg means:

Pricing at $1.90 per kg means:

Put the value of "y" then:

Then the value of "y" is:

So,

In the mixture 36 kg of nuts and 24 kg of cereal.

\(~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\\ P=\textit{original amount deposited}\dotfill & \$5000\\ r=rate\to 5\%\to \frac{5}{100}\dotfill &0.05\\ t=years\dotfill &3 \end{cases} \\\\\\ I = (5000)(0.05)(3) \implies I = 750\)

The value of SSE (sum squared error) is 40 in the given analysis of the variance problem if SST = 120 and SSR = 80. Option b is correct.

Here the words SSE means Sum Squared Error, SST means Sum of Squares Total and SSR means Sum of Square Regression.

In the SSE accuracy measure, errors are squared and then added. It is used when the data points are similar in magnitude.

The formula is SST = SSR + SSE ⇒ SSE = SST - SSR

The given values of the analysis of the variance problem are

SST = 120; SSR = 80

Then, the value of SSE = SST - SSR = 120 - 80 = 40

So, option b is correct.

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a) the inverse function is:

f-1(y) = (y-b)/a

b) f(x) is not one-to-one, it does not have a unique inverse function. Therefore, (F-1)(a) = DNE.

First, let's answer the first part of the question:

To determine whether the function f(x) = ar+b is one-to-one, we need to check if different inputs produce different outputs. Let's suppose that f(x1) = f(x2), where x1 and x2 are distinct inputs. Then, we have:

ar+b = f(x1) = f(x2) = ar+b

Subtracting ar+b from both sides, we get:

ar-ar+b-b = 0

Simplifying, we get:

a(x1 - x2) = 0

Since a is nonzero, this equation implies that x1 = x2, which contradicts our assumption that x1 and x2 are distinct. Therefore, the function f(x) = ar+b is one-to-one.

To find the inverse function of f(x) = ar+b, we can solve for x in terms of y:

y = ar+b

y-b = ar

r = (y-b)/a

x = (y-b)/a

Therefore, the inverse function is:

f-1(y) = (y-b)/a

Now, let's answer the second part of the question:

To find (F-1)(a) for f(x) = x2 + 2x - 1 and a = -4, we set y = -4 and solve for x:

y = x2 + 2x - 1

-4 = x2 + 2x - 1

x2 + 2x - 3 = 0

(x + 3)(x - 1) = 0

x = -3 or x = 1

Since f(x) is not one-to-one, it does not have a unique inverse function. Therefore, (F-1)(a) = DNE.

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In regression, what we want to establish is the exact numerical relationship between the two variables so that, for any given profit centre, we can try to forecast profit based on some causal value. This statement is true.

Regression is a statistical tool that is utilized to establish the relationship between two variables. It examines whether there is a cause-and-effect connection between the two variables. It is commonly used in econometrics and finance to forecast and predict the future of a product or a business. The relationship between two variables is represented graphically on a scatter plot with regression analysis. Whereas time-series and causal models rely on quantitative data, qualitative models attempt to incorporate judgmental or subjective factors into the forecasting model. This statement is false. Qualitative methods, also known as judgmental techniques, rely on expert opinion and subjective information to make forecasts. Whereas time-series and causal models rely on quantitative data, qualitative models attempt to incorporate judgmental or subjective factors into the forecasting model.

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A positively skewed distribution is due to an extremely large number.

A positively skewed distribution is a type of distribution in which the majority of the data values are clustered towards the left side of the distribution, with a tail extending to the right. This means that there are relatively more smaller values in the dataset than larger values. In a positively skewed distribution, the mean of the dataset is typically larger than the median, and the mode may not be a good representation of the central tendency of the data. This is because the presence of a long tail on the right-hand side of the distribution pulls the mean towards the higher values, while the median remains closer to the center of the dataset. Some common examples of positively skewed distributions include income distributions, where there are a few extremely high earners that skew the data towards the right, and test scores, where there may be a few students who perform extremely well and pull the average higher than the median.

Here,

A positively skewed distribution occurs when the tail of the distribution extends to the right, and the majority of the data is clustered towards the left side of the graph. This means that there are relatively more smaller values in the dataset than larger values. One common cause of positive skewness is the presence of extremely large values, also called outliers, in the dataset. These large values pull the mean of the dataset towards the right, resulting in the tail of the distribution stretching in that direction.

Therefore, out of the options provided, the correct answer is "an extremely large number."

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Answer:

Step-by-step explanation:

May I please see the graph?