Use the expression (8x + 2) + (-9x + 7).
a. Find the sum.
b. Reasoning Explain how you know when to combine terms with variables.

Mean of this random variable is 3.14 and standard deviation is 1.82. The mean is calculated by multiplying each value of x by its corresponding probability and then summing the result.

Mean = (-2 * 0.12) + (0 * 0.26) + (3 * 0.28) + (4 * 0.14) + (7 * 0.22)

= 3.14

standard Deviation = [tex]\sqrt{[( (-2)2 * 0.12 ) + (02 * 0.26) + (32 * 0.28) + (42 * 0.14) + (72 * 0.22) - (3.142) ] }[/tex]= 1.82

The mean and standard deviation of a random variable with a given discrete probability distribution can be calculated using the following steps. First, each value of x is multiplied by its corresponding probability and then the results are summed to calculate the mean. For example, for the given discrete probability distribution, the mean is calculated by multiplying -2 by 0.12, 0 by 0.26, 3 by 0.28, 4 by 0.14 and 7 by 0.22 and then summing the results which is 3.14.To calculate the standard deviation, the square of each value of x multiplied by its corresponding probability is summed. Then the square of the mean is subtracted from this result and the square root of the remainder is taken to calculate the standard deviation. For the given probability distribution, the standard deviation is calculated by summing the square of -2 multiplied by 0.12, 0 multiplied by 0.26, 3 multiplied by 0.28, 4 multiplied by 0.14 and 7 multiplied by 0.22. Then the square of the mean which is 3.142 is subtracted from this result and the square root of the remainder is taken which is 1.82.

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Answer:

Equivalent fractions.

Step-by-step explanation:

[tex]\dfrac{1}{2}\\\\\dfrac{2}{4}=\dfrac{2 \div 2}{4 \div 2}=\dfrac{1}{2}\\\\\\\dfrac{4}{8}=\dfrac{4 \div 4}{8 \div 4}=\dfrac{1}{2}[/tex]

So, they are equivalent fractions. Equivalent fractions are fractions with different denominators and numerators representing the same part of a whole.

Answer:

thet are equivalent fractions

Step-by-step explanation:

1/2*2/2=2/4,

2/4*2/2=4/8 or

The probability of at most 2 phone calls received in a given day is roughly 0.021.

Since we are asked for the likelihood of a specific number of phone calls in a given day and are provided the average daily rate of phone calls, we must use the Poisson distribution to solve this problem.

Let represent the average daily call volume, which is provided as = 8.6. Following that, the likelihood of getting no more than two phone conversations in a day is:

P(X ≤ 2) = e^(-λ) * (λ^0/0!) + e^(-λ) * (λ^1/1!) + e^(-λ) * (λ^2/2!)

= e^(-8.6) * (8.6^0/0!) + e^(-8.6) * (8.6^1/1!) + e^(-8.6) * (8.6^2/2!)

≈ 0.021

Therefore, the probability of receiving no more than 2 phone calls in a given day is roughly 0.021.

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Answer:

1. 26*

2. 17*

3. 23*

Answer:

B , 0.75 grams/cm3

Step-by-step explanation:

Crispin's mass measurement (202 grams) has three significant figures, but his volume measurement (270 cm3) only has two significant figures. So when one of these factors is divided by the other, the factor with the lowest number of significant figures takes precedence. This means that the density calculation can only have two significant figures.

The density of an object is its mass divided by its volume:

So, 202 grams ÷ 270 cm3 = 0.75 grams/cm3

(I also did this on study island and the other person made me get it wrong so i got the answer)

The number of different combinations that are possible for Nick, given his baseball hats are A. 4 combinations.

Nick has two options for hats, and two options for sweatshirts/sweaters. To find the number of combinations, we can multiply the number of options for each item.

There are two baseball hats and two clothes - sweatshirt and sweater.

The number of combinations is:

= 2 (hats) x 2 (sweatshirts/sweaters)

= 4 combinations

In conclusion, as regards the number of combinations that Nick can make, there are four.

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The  Equation of Parabola shown in the graph is y=2x².

The general equation of a parabola is given by

y = a(x – h)² + k or x = a(y – k)² +h.

Here (h, k) denotes the vertex. y = a(x – h)² + k is the regular form. x = a(y – k)²+h is the sidewise form.

Given:

We have vertex (0, 0).

As, from the Graph the parabola is open up.

So, it is of the form y= ax², a>0.

Thus, the Equation of parabola is y=2x².

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In mathematical terms, if T is injective, then for any vectors u and v in the domain V, T(u) = T(v) only if u = v. This property is also known as one-to-one correspondence.

One important property of linear operators is their infectivity, which means that the function maps distinct vectors in the domain to distinct vectors in the codomain.

To prove that {Tvi} is also linearly independent, we need to show that if a1T(v1) + a2T(v2) + ... + akT(vk) = 0, then the only solution is a1 = a2 = ... = ak = 0. We can do this by assuming that there exist scalars a1, a2, ..., ak that are not all zero, and show that this leads to a contradiction.

Suppose that

=> a1T(v1) + a2T(v2) + ... + akT(vk) = 0,

where not all of the ai's are zero. Then, we can write this as

=> T(a1v1 + a2v2 + ... + akvk) = 0.

Since T is injective, this implies that a1v1 + a2v2 + ... + akvk = 0.

Now, let's move on to the second part of the problem statement, which deals with the surjectivity of the linear operator T.

In other words, if T is surjective, then for any vector w in the codomain V, there exists a vector v in the domain V such that T(v) = w.

If {vi} spans V, then every vector in V can be expressed as a linear combination of the {vi}'s. In other words, for any vector u in V, there exist scalars c1, c2, ..., ck such that

=> u = c1v1 + c2v2 + ... + ckvk.

To prove that {Tvi} also spans V, we need to show that every vector w in V can be expressed as a linear combination of the T(vi)'s.

Then, we can express v as a linear combination of the {vi}'s:

=> v = c1v1 + c2v2 + ... + ckvk.

Applying T to both sides, we get:

w = T(v) = T(c1v1 + c2v2 + ... + ck

W = c1T(v1) + c2T(v2) + ... + ckT(vk)

This shows that w can be expressed as a linear combination of the T(vi)'s, which means that {Tvi} also spans V.

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The required line is y = -(3/2)x - 6 which is perpendicular and shifted down 8 units.

Perpendicular lines are two lines that cross one other and create a 90-degree angle. Two lines are perpendicular if the product of their slopes is -1.

The slope-intercept form of a line is y = (2/3)x + 2.

To find the slope of the perpendicular line, we simply need to negate the reciprocal of the original line's slope.

The slope of the original line is 2/3. The slope of the perpendicular line is therefore -3/2.

To shift the line down 8 units, we simply need to subtract 8 from the y-intercept.

The slope-intercept form of the line perpendicular to y = (2/3)x + 2 and shifted down 8 units is:

y = -(3/2)x + 2 - 8 = -(3/2)x - 6

So the line that is perpendicular and shifted down 8 units is y = -(3/2)x - 6.

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Answer: Solution set of the quadratic equation is, Empty set

Step-by-step explanation:

Given the quadratic equation:  

Subtraction property of equality states that you subtract the same number to both sides of an equation.

Subtract both sides by 1 we get;

Simplify:

Division property of equality states that you divide the same number to both sides of an equation.

Divide both sides by 6 we get;

Simplify:

For any x in real number there does not exist any number x which satisfy

, therefore, there is no solution for this set of the quadratic inequality or in other word we can say that set of the solution is Empty set.

I'm sorry, there is no image or diagram provided to identify the shaded region. Could you please provide more information or a visual aid for me?

The expected value of an unbiased estimator is equal to the parameter whose value is being estimated. A) True B) False . the answer is false

Answer:

38 & 27 & 147

Step-by-step explanation:

4) 38cm²

5*4 = 20cm²

2*9 = 18cm²

5) 27m²

6*6 = 36m²

3*3 = 9m²

6) 147in²

14*14 = 196cm²

7*7 = 49in²

Answer:

4)  38 cm²

5)  27 m²

6)  147 in²

Step-by-step explanation:

To calculate the area of each given figure, subtract the area of the cut-out rectangle (marked in blue on the attached diagram) from the area of the larger rectangle.

[tex]\boxed{\begin{minipage}{5cm}\underline{Area of a rectangle}\\\\$A=w\cdot l$\\\\where:\\ \phantom{ww} $\bullet$ \quad $w$ is the width.\\ \phantom{ww} $\bullet$ \quad $l$ is the length.\\\end{minipage}}[/tex]

[tex]\begin{aligned}\textsf{Total Area}&=\textsf{Larger rectangle}-\textsf{Cut-out rectangle}\\&=9 \cdot 6- (9-5)\cdot 4\\&=9 \cdot 6- 4\cdot 4\\&=54-16\\&=38\; \sf cm^2\end{aligned}[/tex]

[tex]\begin{aligned}\textsf{Total Area}&=\textsf{Larger rectangle}-\textsf{Cut-out rectangle}\\&= 6\cdot 6- 3\cdot 3\\&=36-9\\&=27\; \sf m^2\end{aligned}[/tex]

[tex]\begin{aligned}\textsf{Total Area}&=\textsf{Larger rectangle}-\textsf{Cut-out rectangle}\\&= 14\cdot 14- 7\cdot 7 \\&=196-49\\&=147\; \sf in^2\end{aligned}[/tex]

The requried a measure of the exterior angle ∠4 = 63°.

The triangle is a geometric shape that includes 3 sides and the sum of the interior angle should not be greater than 180°

Here,

As we know that for a triangle, the sum of the remote interior angle is equal to the measure of the exterior angle.

So, from the figure.

31 + 32 = ∠4

∠4 = 63°

Thus, the requried measure of the exterior angle ∠4 = 63°.

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The probability that a randomly selected person will have a z-score less than 2.00 is about 97.72%. (option closest: 0.9750)

To utilize the experimental rule, we want to know the z-score comparing to a given likelihood. The z-score addresses the quantity of standard deviations an information point is from the mean.

Utilizing the mean and standard deviation given, we can switch the crude score of somebody's pay over completely to a z-score utilizing the recipe:

z = (x - μ)/σ

z = (64,000 - 64,000) / 12,000 = 0

where x is the crude score (family pay), μ is the mean, and σ is the standard deviation.

To find the likelihood that somebody chose indiscriminately will have a z-score under 2.00, we can utilize a standard typical dispersion table or number cruncher to track down the region under the bend to one side of 2.00. This relates to the likelihood of a haphazardly chosen individual having a pay under 2 standard deviations over the mean.

The exact decide states that for an ordinary dissemination with a symmetric recurrence conveyance, around 68% of the information falls inside one standard deviation of the mean, around 95% falls inside two standard deviations of the mean, and around 99.7% falls inside three standard deviations of the mean.

Since we are searching for the likelihood of a z-score under 2.00, which is inside two standard deviations of the mean, we can utilize the experimental decide and gauge that the likelihood is around 95%.

Nonetheless, on the off chance that we need a more exact response, we can utilize a standard typical dissemination table or mini-computer to track down the region under the bend to one side of 2.00. The region under the standard typical dispersion bend to one side of 2.00 is 0.9772, which relates to a likelihood of 0.9772 or 97.72%. Accordingly, the right response is roughly 0.9772 or 97.72%.

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The correct statements regarding the linear functions are given as follows:

The slope-intercept definition of a linear function is given as follows:

y = mx + b.

In which:

For Company P, the function is given as follows:

y = 30x + 50.

Meaning that:

From the table, for company R, the function is given as follows:

y = 25x + 75.

Meaning that:

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Given that the area of the region bounded by the curve f(x) and x-axis from x=4 to x=10 is 13/5, the average value of the negative-valued function y=f(x) over the interval [4,10] is -13/30.

The average value of a function f(x) over an interval [a,b] is given by:

average value = (1/(b-a)) * integral from a to b of f(x) dx

In this case, we are given that the function y=f(x) is negative-valued, and the area of the region bounded by the curve and x-axis from x=4 to x=10 is 13/5. This means that the integral of f(x) over the interval [4,10] is equal to -13/5:

[tex]\int\limits^{10}_4 \, f(x) dx[/tex] = -13/5

To find the average value of f(x) over this interval, we divide this integral by the length of the interval:

average value = (1/(10-4)) * [tex]\int\limits^{10}_4 \, f(x) dx[/tex]

             = (1/6) * (-13/5)

             = -13/30

Therefore, the average value of the negative-valued function y=f(x) over the interval [4,10] is -13/30. This means that if we were to draw a horizontal line at the height of -13/30 over the interval [4,10], the area between this line and the x-axis would be equal to the area of the region bounded by the curve f(x) and x-axis over the same interval.

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The simplest way to calculate the surface area of a polyhedron, though, remains to simply sum the areas of the polygons that make up its faces. The surface area of a sphere has a very interesting formula. It depends solely on the radius of the sphere. The surface area of a sphere is equal to 4Π times the square of the radius of the sphere: 4Πr2.

maybe if you ask politely

[tex]A =\left[\begin{array}{ccc}3&0\\-2&1\\\end{array}\right][/tex] , [tex]B =\left[\begin{array}{ccc}-2&0\\2&0\\\end{array}\right][/tex] so that A,B are non-invertible matrices and  A+B is invertible.

An invertible matrix is a matrix in given square matrix A of order n × n is called invertible if there exists another n × n square matrix B such that, AB = BA = Iₙ, where Iₙ is an identity matrix of order n × n.

A non-invertible matrix is a matrix that does not have an inverse, i.e. non-invertible matrices do not satisfy the requisite condition to be invertible.

We have to find non-invertible matrices A,B such that A+B is invertible

so, A =[tex]\left[\begin{array}{ccc}3&0\\-2&1\\\end{array}\right][/tex]

and B =[tex]\left[\begin{array}{ccc}-2&0\\2&0\\\end{array}\right][/tex]

AB = [tex]\left[\begin{array}{ccc}-6&0\\6&0\\\end{array}\right][/tex]  

Therefore A and B matrix are non- invertible

A + B = [tex]\left[\begin{array}{ccc}1&0\\0&1\\\end{array}\right][/tex]

A square matrix in which every element except the principal diagonal elements is zero is called a Diagonal Matrix.

so, A,B neither is a diagonal matrix and A,B are not scalar multiples of each other.

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Answer:

Below

Step-by-step explanation:

You have ONE equation and TWO unknowns, so there is infinite solutions for a and c......you cannot solve for a specific a and c unless you have another equation relating the two or a definition of one of them.

 You can Solve for a

  20a + 15 c = 340

     20 a = 340-15c

        a = ( 340 -15c) / 20 = 17 - 3/4 c

Similarly:

   20 a + 15 c = 340

  15c = 340 - 20 a

c = (340-20a)/15

The probability that a defective part made at this factory was made on the first assembly line is 0.299 or 29.9%,

This issue can be resolved using Bayes' theorem. Let L1, L2, and L3 represent the events that the component was produced on the first, second, and third assembly lines, respectively, and let D represent the event that a defective part is produced. Next, given that the part is defective, we want to determine P(L1 | D), which is the likelihood that the component was made on the first production line.

We can determine P(D), the overall likelihood of creating a defective part, using the rule of total probability:

P(D) = P(D | L1) P(L1) + P(D | L2) P(L2) + P(D | L3) P(L3)

= 0.02 × 0.29 + 0.04 × 0.27 + 0.01 × 0.44

= 0.0195

next, we can determine P(L1 | D) using Bayes' theorem:

P(L1 | D) = P(D | L1) P(L1) / P(D)

= 0.02 × 0.29 / 0.0195

= 0.299

As a result, there is a 29.9% chance that a defective component produced at this factory was made on the first assembly line, or about 0.299 of a chance.

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By the face of the pyramid that lies in a base of the prism and the face of the pyramid, h2 = 108°

Let B and C be the vertices adjacent to A on the same base as A, and let D be the last vertex of the triangular pyramid. Then angle CAB = 120. Let x be the foot of the altitude from A to line BC. Then since triangle ABX is a 30-60-90 triangle, AX=6. Since the dihedral angle between triangle ABC  and triangle BCD is 60 degree, triangle AXD is a 30-60-90 triangle and 

[tex]AD = 6 \sqrt{3} = h[/tex]

Therefore,

[tex] {h}^{2} = 108[/tex]

A triangular prism is a three-sided prism that has three faces joining the corresponding sides of its triangular base, translated copy, and polyhedron construction. If the sides of a right triangular prism are not rectangular, the prism is oblique. Having square sides and equilateral bases, a uniform triangular prism is a right triangle.

It is, in essence, a polyhedron with three faces, all of whose surface normals are in the same plane (which need not be parallel to the base planes), and two of whose faces are parallel. It is a parallelogram that has these three faces. The same triangle can be seen in all cross-sections that are perpendicular to the base faces.

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Jack may not be obligated to pay Sam the $100 reward because he revoked the offer before Sam found the wallet.

The unitary method is a method for solving a problem by the first value of a single unit and then finding the value by multiplying the single value. Unitary method is a technique by which we find the value of a single unit from the value of multiple devices and the value of more than one unit from the value of a single unit. It is a method that we use for most of the calculations in math.

We are given that;

The amount of reward= $100

Now,

An offer can be revoked at any time before acceptance, and the revocation must be communicated to the offeree. In this case, Jack placed a second ad in the same newspaper revoking his offer before Sam found the wallet. Therefore, Sam did not accept the offer before it was revoked.

Additionally, Sam may not have provided consideration for the reward. Consideration is something of value given in exchange for a promise. In this case, Sam found the wallet before the reward was offered, so he did not provide consideration for the reward when he returned the wallet.

since the offer was revoked before acceptance and Sam did not provide consideration for the reward,

Therefore, by unitary method Jack may not be obligated to pay Sam the $100.

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The average water level at the dock between 4 and 19 is 17.5 feet, calculated by taking the average of the water level at 4 and 19.

H(4) = 5 sin (pi/6 (4 - 6)) + 19 = 17

H(19) = 5 sin (pi/6 (19 - 6)) + 19 = 18

Average water level = (17 + 18)/2 = 17.5

The given equation is H(t) = 5 sin (pi/6 (t - 6)) + 19. This equation represents the water level at a dock over a 24 hour period, where t represents the time in hours. To calculate the average water level at the dock at 4 and 19, we need to first calculate the water level at 4 and 19. To do this, we substitute 4 and 19 in the equation in place of t. This gives us H(4) = 5 sin (pi/6 (4 - 6)) + 19 = 17 and H(19) = 5 sin (pi/6 (19 - 6)) + 19 = 18. The average water level is then calculated by taking the average of these two values, which is (17 + 18)/2 = 17.5. This is the average water level at the dock between 4 and 19.

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Answer: The store paid $84 to purchase the skateboard

Step-by-step explanation:

If the selling price of the skateboard is $147 and the markup is 75%, we can find the cost of the skateboard by working backwards from the selling price.

Let's start by calculating the original cost of the skateboard before the markup was applied. We can do this by dividing the selling price by 1 plus the markup percentage as a decimal:

original cost = selling price / (1 + markup percentage)

Converting the markup percentage to a decimal:

markup percentage = 75% = 0.75

original cost = 147 / (1 + 0.75)

original cost = 147 / 1.75

original cost = 84

The point-slope form of data contained in this table is y - 15 = 8.3(x - 7.2).

The slope-intercept form of data contained in this table is y = 8.3x - 10.

In Mathematics, the point-slope form of a straight line can be calculated by using this mathematical expression:

y - y₁ = m(x - x₁) or y - y₁ = (y₂ - y₁)/(x₂ - x₁)(x - x₁)

Where:

At data point (7.2, 15), a linear equation in standard form for this line can be calculated by using the point-slope form as follows:

y - y₁ = (y₂ - y₁)/(x₂ - x₁)(x - x₁)

y - 15 = (35 - 15)/(4.8 - 7.2)(x - 7.2)

y - 15 = 8.3(x - 7.2)

y - 15 = 8.3x - 25

y = 8.3x - 10

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The area of the shaded region is 0.725746882.

The probability distribution of random variables is described using the cumulative distribution function. The probability for a discrete, continuous, or mixed variable may be described using it. The cumulative probability for a random variable is calculated by adding the probability density function.

Given:

The graph depicts the IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15. 91.

From the diagram,

the critical value is 91.

The formula to calculate the z-score is,

z = (x - u) / s,

Substituting the given values to the formula,

the given values are;

x = critical value = 91

u = mean = 100

s = standard deviation = 15

Thus,

z = (x - u) / s

z = -0.6

P(z > -0.6 ) = 0.725746882

Therefore, the area is 0.725746882.

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Step-by-step explanation:

To find the greatest common factor (GCF) of the expression (8 + 12), we need to first simplify the expression by finding the sum, which is 20. Therefore, the GCF of (8 + 12) is simply the GCF of 20, which is 20.

To rewrite the expression as a multiple of a sum of two whole numbers with no common factor, we can factor out the GCF of 4 from both 8 and 12, giving us:

(8 + 12) = 4(2 + 3)

The expression (8 + 12) is thus a multiple of the sum of the whole numbers 2 and 3, which have no common factor.