No Extraneous solution
The given equation is
( 7x + 6 ) ^ 1/2 - (9 + 4x ) ^ 1/2 = 0
We have to find the value of x
[tex]\sqrt{7x + 6}[/tex] = [tex]\sqrt{9 + 4x}[/tex]
Squaring both sides of the equation
[tex](\sqrt{ 7x + 6} )^{2}[/tex] = [tex](\sqrt{9 + 4x})^{2}[/tex]
7x + 6 = 9 +4x
3x = 3
x = 1
To know whether the value of x is the extraneous solution or not, put the value of x in the equation
[tex]\sqrt{7 * 1 + 6}[/tex] -[tex]\sqrt{ 9 + 4 * 1}[/tex] = 0
[tex]\sqrt{13}[/tex] - [tex]\sqrt{13}[/tex] =0
0 = 0
Therefore there is no extraneous solution to the equation as x = 0 is the solution of the equation.
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You use 130 feet of fencing to go around a rectangular pool and patio. The length of the area is 9 more than the width. What are the dimensions of the fence?
The dimensions of the fencing is 28 ft and 37 ft respectively.
How to find the dimension of the rectangular fence?He use 130 feet of fencing to go around a rectangular pool and patio.
The length of the area is 9 more than the width.
The dimension of the fence can be found as follows:
Therefore,
perimeter of the rectangular fence = 2(l + w)
where
l = lengthw = widthHence,
l = 9 + w
perimeter of the rectangular fence = 2(w + 9 + w)
perimeter of the rectangular fence = 2(2w + 9)
130 = 4w + 18
130 - 18 = 4w
112 = 4w
w = 112 / 4
w = 28 ft
l = 9 + 28 = 37 ft
Therefore, the width and length of the fencing is 28 ft and 37 ft respectively.
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which of the following is equal to 16%
Answer:0.16=16%
Step-by-step explanation: [tex]\frac{0.16}{100}[/tex]
the 100 is directly under the point so the zero will cancel out leaving= [tex]\frac{16}{100}[/tex]
And [tex]\frac{16}{100}[/tex] equals to 16%
if we had a value "z", and we'd like to know how much is 16% of "z", well
[tex]\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{16\% of z}}{\left( \cfrac{16}{100} \right)z}\implies 0.16z[/tex]
so we can use the "factor" of 0.16, to get the 16% of any value,
since 0.16 is the decimal representation of the percentage of 16.
hmmm what is 16% of 50 anyway?
[tex]\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{16\% of 50}}{\left( \cfrac{16}{100} \right)50}\implies 8[/tex]8 out of 50
how much is 16% of 25 anyway?
[tex]\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{16\% of 25}}{\left( \cfrac{16}{100} \right)25}\implies 4[/tex]4 out of 25
A teacher wishes to know whether the males in his/her class have more conservative attitudes than the females. a questionnaire is distributed assessing attitudes.
a. is this a sampling or a census?
b. is this an observational study or an experiment?
c. are there any possible sources of bias in this study?
Descriptive statistics is the correct answer.
Descriptive statistics are numbers that are used to summarize and describe data. The word "data" refers to the information that has been collected from an experiment, a survey, a historical record, etc. (By the way, "data" is plural. One piece of information is called a "datum.") If we are analyzing birth certificates, for example, a descriptive statistic might be the percentage of certificates issued in New York State or the average age of the mother. Any other number we choose to compute also counts as a descriptive statistic for the data from which the statistic is computed. Several descriptive statistics are often used at one time to give a full picture of the data.
Descriptive statistics are just descriptive. They do not involve generalizing beyond the data at hand. Generalizing from our data to another set of cases is the business of inferential statistics, which you'll be studying in another section. Here we focus on (mere) descriptive statistics.
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Calculate the volume of the cylinder below
question is in the picture
The solution to the system of equations using substitution is: x = 3 and y = -4.
How to Solve a System of Equations Using Substitution?Given the system of equations:
-7x - 2y = -13 -----> equation 1
x - 2y = 11 -----> equation 2
Rewrite equation 2
x - 2y = 11
x = 11 + 2y
Substitute x = (11 + 2y) into equation 1
-7(11 + 2y) - 2y = -13
-77 - 14y - 2y = -13
-77 - 16y = -13
-16y = -13 + 77
-16y = 64
y = -4
Substitute y = -4 into equation 2
x - 2(-4) = 11
x + 8 = 11
x = 11 - 8
x = 3
Therefore, the solution to the system of equations using substitution is: x = 3 and y = -4.
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there are 500 students and 325 say they have too much homework what percent said they have too much homework
Answer:
65%
Step-by-step explanation:
To find percentage, we take the fraction of the total and multiply it by 100.
[tex]\frac{325}{500} \times=\frac{325}{5}=65[/tex]
Answer:
[tex]153.84\%[/tex]
Step-by-step explanation:
[tex] 1. \: \frac{500}{3.25} \\ 2. \: 153.84\%[/tex]
I need help can someone help me.
10 order of small popcorn Should be made to keep the cost same at both the theaters
The theater P charges Admission fee of $10 and small popcorn order of $4.55
The theater Q charges Admission fee of $8 and small popcorn order of $4.75
We need to find the number of order of small popcorn so that the cost remain same
Let the number of small popcorn order be x
Then we can form the algebraic equation as
10 + 4.55x = 8 + 4.75x
now we should simplify the equation
10- 8 = 4.75x-4.55x
2= .2x
x = 2/0.2
x = 10
Hence , 10 order of small popcorn Should be made to keep the cost same at both the theaters
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d.
Rule: Output =
Input
-2
0
3
4
8
er
Process
Ox
3x
4x
8+
Output
-15
-5
10
15
35
Answer:
20000fish deeen of fatherlaal yyyeeeeepee classes link hahahaha nnooooo bb bot play fff 15 sec wait ok now ans free fire max ok u noobbot
Let f(x)=x-4 and g(x)=x²-16 . Perform each function operation and then find the domain. f(x)+g(x)
The domain for g (x) + f (x) = x² + x - 20 will be all real numbers when f (x) = x - 4 and g (x) = x² - 16.
We are given the two functions as:
f (x) = x - 4
g (x) = x² - 16
Now, first, we need to add f (x) from g (x).
So, we get that:
g (x) + f (x) = x² - 16 + (x - 4)
g (x) + f (x) = x² - 16 + x - 4
g (x) + f (x) = x² + x - 20
Now, the domain of the function will be all real numbers as it will be defined for all the real numbers.
Therefore, we get that the domain for g (x) + f (x) = x² + x - 20 will be all real numbers when f (x) = x - 4 and g (x) = x² - 16.
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What is the value of the expression 38x − 17 if x is equal to −5?
Answer:
-207
Step-by-step explanation:
38x - 17
38(-5) - 17
-190 - 17
-207
*Please mark brainliest answer
Answer:-173
Step-by-step explanation:
38x - -17
38 multiplied by -5 equals -190
-190 - -17 equals -173
Will the answer to the subtraction problem below be odd or even?
5415-3556 = ?
O
A. Odd
B. Even
Answer:
Odd
Step-by-step explanation:
The answer to the equation is 1,859, making the answer odd.
I need help finding these, all of them not just one
One pair of vertical angles are ∠1 and ∠4.
One pair of angles that are congruent are ∠3 and ∠6.
One pair of angles that are congruent are ∠3 and ∠6.
What are vertical angles, linear pairs and congruency?Vertical angles are the angles opposite each other when two lines cross.
Vertical angles are congruent. This means vertical angles are equal to each other.
Therefore, one pair of vertical angles are ∠1 and ∠4.
Linear pair of angles are formed when two lines intersect each other at a single point.
Therefore, one pair of linear pair angles are ∠6 and ∠8.
Angles are congruent when they are the same. Congruent angles includes corresponding and alternate angles.
Therefore, one pair of angles that are congruent are ∠3 and ∠6.
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Will mark branilest
The function f(x) = ( x + 7)³ - 8 will shift left 7 units along x axis and will shift down 8 units along y axis to its parent function g(x) = x³.
What is translation?By translation, we can stretch, shrink and shift graphs along the x-y coordinate.
We know a parent function is a function that is in its simplest form without any translation.
Given f(x) = (x + 7)³ - 8 and its parent function is g(x) = x³.
Now let us break this function f(x),
f(x) = ( x+ 7)³ implies x + 7 = 0 ⇒ x = -7.
So, x will shift 7 units to the left along the x-axis.
f(x) = ( x + 7)³ - 8, This will shift the function down 8 units along y-axis.
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The midpoint of \overline{\text{AB}}
AB
is M(3, -4)M(3,−4). If the coordinates of AA are (8, -5)(8,−5), what are the coordinates of BB?
(-2, -3) represents the coordinate of point B from the given expression.
Midpoint of coordinatesThe formula for calculating the midpoint of coordinates is expressed as shown below:
Midpoint = {(x₁+x₂)/2, (y₁+y₂)/2}
Given the following parameters
Midpoint = (3, -4)
A = (8,-5)
Required
Coordinate point B
Substitute the given parameters
3 = (8+x₂)/2
3(2) = 8+x₂
6 = 8+x₂
x₂ = -2
Similarly
-4 = (-5+y₂)/2
-4(2) = -5+x₂
-8 = -5 +y₂
y₂ = -3
Hence the coordinate of point B from the given expression is (-2, -3)
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Graph the piecewise-defined function. What are the domain and range? Over what intervals is the function increasing or decreasing?
2x + 5, -6 ≤ x ≤ -2 2x²-7, -2 < x < 1 1 ≤ x ≤ 3
a. f(x) = H - 4 - X, 1. -8 8 4 -4 O -4 H -8 4 X 1.00 8
Answer:
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Pakistan
How do you solve this equation
-1 = -1 + (p/8)
The solution to the given equation -1 = -1 + (p/8) is p = 0.
What is the solution to the given equation?Given the data in the question;
-1 = -1 + (p/8)p = ?Solve for p to determine the solution to the equation.
-1 = -1 + (p/8)
Rewrite the equation as;
-1 + (p/8) = -1
Next, move all terms containing p to the left side and all constants to the right side of the equation.
-1 + (p/8) = -1
(p/8) = -1 + 1
Add -1 and 1
p/8 = -1 + 1
p/8 = 0
p = 0 × 8
p = 0
The solution to the given equation -1 = -1 + (p/8) is p = 0.
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whats the answer to −x2+6zy=
Answer:
- 2(x - 3zy)
Step-by-step explanation:
Estimate 3 √ 70 to the nearest integer.
The value of the expression 3√70 to the nearest integer will be 25.10.
What is the value of the expression?When the relevant factors and natural laws of a mathematical model are given values, the outcome of the calculation it describes is the expression's outcome.
PEMDAS rule means the Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This rule is used to solve the equation in a proper and correct manner.
The expression is given below.
⇒ 3√70
We know that the value of √70 will be 8.3666. Then the value of the expression will be given as,
⇒ 3√70
⇒ 3 x 8.3666
⇒ 25.0998 ≈ 25.10
The value of the expression 3√70 to the nearest integer will be 25.10.
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2.39 repeating as a mixed number
15 A railway station has two platforms. Trains stop at the northbound platform every 10 minutes. Trains stop at the southbound platform every 18 minutes Two trains stopped together at 1512 (a) Work out the next time two trains stop together at this station.
The answer is 190m.
The faster train is 160 m long and crosses a lamp post in 12 seconds.
The speed of the faster train = 16012 = 403 m/s
Given that, the speed of the other train is 6 km/hr (53 m/s) less than the faster one. [we can convert speeds from km/h to m/s by multiplying with 5/18]
The speed of the slower train = 353 m/s.
Given that, the two trains cross each other in 14 seconds when running in opposite directions along parallel tracks.
tracks.
Relative speed = total length of two trains time taken to cross each other
25m/s = 160+ length of second train 14
Length of the second train = 190m.
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Use natural logarithms to solve each equation. e x=18
2.89 is the value of x in equation [tex]e^x[/tex] = 18 solved by using natural logarithms.
We have been asked to find x in [tex]e^x[/tex] = 18 using natural logarithms
⇒ [tex]e^x[/tex] = 18
⇒ x = ㏑ (18)
⇒ x = 2.89
What is a natural logarithm?A number's natural logarithm is its logarithm to the base of the transcendental and irrational number e, which is roughly equivalent to 2.718281828459.
Typically, the natural logarithm of x is denoted by the symbols ln x, loge x, or, if the base e is implicit, just log x. When adding parentheses for clarity, the values ln(x), loge(x), or log (x). In order to avoid ambiguity, this is notably done when the argument to the logarithm is not a single symbol.
The power to which e would need to be raised in order to equal x is the natural logarithm of x.
For instance, e2.0149... = 7.5, thus ln 7.5 equals 2.0149.
Since e1 = e, the natural logarithm of e itself, or ln e, is equal to 1, while the natural logarithm of 1 is 0, since e0 = 1.
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Correct questionUse natural logarithms to solve each equation.
[tex]e^x[/tex] = 18
which is greater 5/2 or 7/4?
Answer:
Comparamos los dos números decimales anteriores, y podemos ver que 2.5 es mayor que 1.75. Por lo tanto, 5/2 es mayor que 7/4
Step-by-step explanation:
Answer:
7/4 because if you divide them both, 7/4's decimal will be greater
Use v=-0.0098 t+c ln R , where v is the velocity of the rocket, t is the firing time, c is the velocity of the exhaust, and R is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. Find the velocity of a spacecraft whose booster rocket has a mass ratio of 20 , an exhaust velocity of 2.7km/s, and a firing time of 30 s . Can the spacecraft achieve a stable orbit 300km above Earth?
The velocity of the spacecraft is 7.7025 km/s as calculated with the help of mass ratio.
What is mass ratio of a rocket?An indicator of a rocket's effectiveness is its mass ratio.It describes the ratio of the rocket's wet mass to its dry mass, or how much more massive the vehicle is with propellant than without.Given:
v = - 0.0098(t) + c (ln (R) ), where:v = maximum shuttle velocityt = firing timec = velocity of exhaustR = mass ratioTo find: Velocity of the spacecraft (v) = ?
Finding:
Here, c = 2.7 km/s, t = 30s, R = 20
On substituting the values of 'R', 't', 'v', we get:
v = -0.0098 ( 30) + 2.7 ( ln (20))
=> v = - 0.294 + 2.7 (2.995)
=> v = 7.7025 km/s
Hence, the velocity of the spacecraft is 7.7025 km/s as calculated with the help of mass ratio.
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Open-Ended Write a problem that could be modeled with y=20(1.1) x
The problem that can be defined by the function is:
A cat breeding company has 20 cats initially. The number of cats increases by 10% each year. Write a function for the exponential growth of the number of cats over the years. How many cats will the company have after 10 years?
A quantity must vary by a specific percentage each time period in order for growth or decay to be exponential.
With the function displayed to the right, you may represent exponential growth or decay.
A(x) = a( 1 + r)ˣ
Where A is the amount after x time periods, a is the initial amount and x is the number of time periods.
Consider the modeled function y = 20(1.1)ˣ.
Now, y = 20 × ( 1 + r)ˣ
f(x) = 20 × ( 1 + r)ˣ
Comparing the above equation with A(x) = a( 1 + r)ˣ
The initial amount is 20 and it increases 1 + r = 1.1.
Therefore, r = 0.1 = 10 %
Let's say we are starting a cat breeding company. Initially, we have 20 cats.
So, the problem for the function is:
A cat breeding company has 20 cats initially. The number of cats increases by 10% each year. Write a function for the exponential growth of the number of cats over the years. How many cats will the company have after 10 years?
So, a = 20, x = 10, and r = 10% = 0.1
Therefore,
A(x) = a( 1 + r)ˣ
y = a( 1 + r)ˣ
y = 20( 1 + 0.1 )ˣ
y = 20( 1.1)¹⁰
y = 20 × 2.594
y = 52
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If z=30 when x=3 and y=2 , write the function that models the relationship.
z varies jointly with x and y .
According to the question, to calculate the relationship model of the given equations which are as follows:
[tex]z=30[/tex] when [tex]x =3 ; y=2[/tex]
And the condition is z varies jointly with x and y which can be represented as: [tex]z = \frac{k}{xy}[/tex]
Substituting the values to get the final expression:
[tex]30 = \frac{k}{(3)(2)} =\frac{k}{6}[/tex]
[tex]k=180[/tex]
Substitute the value of 'k' in the original equation. And the final expression is: [tex]z = \frac{180}{xy}[/tex]
What is function?
In mathematics, function can be defined as an expression or the rule or the law. It defines the relationship between dependent variable and the independent variable.
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I need this with overtime pay.
Kerry worked 46 hours last week. His hourly rate is $9.60. He has the following deductions taken from his pay: federal income tax at the rate of 10 percent, Social Security tax at the rate of 6.2 percent, Medicare tax at the rate of 1.45 percent, health insurance premiums of $12.20, and union dues of $9.50. Kerry’s net pay for last week was $. Hide Feedback Incorrect Check My Work Feedback Gross pay includes regular hours times regular pay, plus overtime hours times overtime pay. The overtime pay rate is 1½ times the regular rate of pay. Deductions—both required and voluntary—are subtracted from gross pay to compute net pay. (Round to the nearest cent for all calculations.)
Answer:
here to try to help!
Step-by-step explanation:
346.96 why? Kerry was not payed at the overtime for extra hours hope it helped!
Evaluate each function at the specified value
f(x)=7x-5;x=6
Solve the system of equations using a matrix
-x+2 y+z=0
y=-2 x+3
z=3 x
The solution of x , y , z are 3 , -3 , 9 respectively using matrix.
Solving the system of linear equations using the inversion method consists of two new matrices . Matrix A: representing variables , matrix B: represents a constant The system of equations can be solved by matrix multiplication which is given by [tex]X=A^{-1}B[/tex] ..(1)We have given three equations -x+2 y+z=0 , y =-2 x+3 , z = 3 x
This can be written as AX=B
Where [tex]A=\left[\begin{array}{ccc}-1&2&1\\2&1&0\\-3&0&1\end{array}\right][/tex] and [tex]X=\left[\begin{array}{ccc}x\\y\\z\end{array}\right][/tex] [tex]B=\left[\begin{array}{ccc}0\\3\\0\end{array}\right][/tex]
A is the coefficient matrix, X the variable matrix and B the constant matrix.
[tex]|A|=-1(1)-2(2)+1(3)\\|A|=-1-4+3=-2[/tex]
Since , [tex]|A|\neq 0[/tex]
Hence, the system of equations is consistent and has a unique solution
A inverse is given by [tex]\frac{adjA}{|A|}[/tex] .....(2) and adj(A) is given by [tex]AdjA=C^T[/tex] ...(3)
Minor of matrix A will be
[tex]M_{11}=1\\M_{12}=2\\M_{13}=3\\M_{21}=2\\M_{22}=2\\M_{23}=6\\M_{31}=-1\\M_{32}=2\\M_{33}=-5[/tex]
Then Co - factor will be
[tex]C_{11}=1\\C_{12}=-2\\C_{13}=3\\C_{21}=-2\\C_{22}=2\\C_{23}=-6\\C_{31}=-1\\C_{32}=-2\\M_{33}=-5[/tex]
Matrix C will be represented by
[tex]C=\left[\begin{array}{ccc}1&-2&3\\-2&2&-6\\-1&-2&-5\end{array}\right][/tex]
Transpose of matrix C will be represented by
[tex]C^T=\left[\begin{array}{ccc}1&-2&-1\\-2&2&-2\\3&-6&-5\end{array}\right][/tex]
Then , putting this value in equation (3) , we get
[tex]adjA=C^T\\adjA=\left[\begin{array}{ccc}1&-2&-1\\-2&2&-2\\3&-6&-5\end{array}\right][/tex]
Putting the value of |A|=-2 and adjA in equation (2) , we get
[tex]A^{-1}=\frac{1}{-2}\left[\begin{array}{ccc}1&-2&-1\\-2&2&-2\\3&-6&-5\end{array}\right][/tex]
Putting the value of A inverse in equation (1) , we get
[tex]X=\frac{1}{-2}\left[\begin{array}{ccc}1&-2&-1\\-2&2&-2\\3&-6&-5\end{array}\right]\left[\begin{array}{ccc}0\\3\\0\end{array}\right]\\\\\\\left[\begin{array}{ccc}x\\y\\z\end{array}\right]=\frac{-1}{2} \left[\begin{array}{ccc}-6\\6\\-18\end{array}\right] \\\\\\\left[\begin{array}{ccc}x\\y\\z\end{array}\right]=\left[\begin{array}{ccc}3\\\ -3 \\9\end{array}\right][/tex]
On comparing , we get x = 3 , y = -3 , z = 9
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What is the inverse of y=4 x²+5 ? Is the inverse a function?
The inverse of the function y=4 x²+5 is y = √((x-5)/4).
What exactly is a function's inverse?Inverse functions are those that cancel one another out. In other words, if g(x) is f's inverse, then f(g(x)) = g(f(x)) = x. (x). Given an equation for which we want the inverse, we have a fantastic method we can utilize to do this.
Not every function has a counterpart. If f(x) has an inverse, it is clear to see that it will never again have the same value. We give this resource a special name.
A function (f(x)) is said to be one-to-one if each member of the range corresponds to exactly one element of the domain.
Given,
We have a function,
y=4 x²+5
subtracting 5 from each side.
⇒ y - 5 = 4 x²
Divide by 4 and then either
⇒ x² = (y - 5) / 4
⇒ x = √((y-5)/4)
Just change the labels now, x to y.
⇒ y = √((x-5)/4)
So, the inverse of given function is y = √((x-5)/4)
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Solve each equation.
3x =9
Solution of this polynomial equation is x = 3
What are polynomial equations ?In mathematics, polynomial equation can be defined as the equation which consist of coefficient, variables and exponents. A polynomial equation has positive numbers as their exponent which is also known as its degree. All the equations such as quadratic equation, cubic equation which has non negative number as their powers are part of polynomial equation.
Types of polynomial equations :
Monomial equationBinomial equationCubic EquationsLinear Polynomial Quadratic PolynomialSome examples of polynomial equation are :
2x+53x = 93x² + 5x+19(x-3)³According to question,
3x = 9
=> 3x / 3 = 9 /3
=> x = 3
Thus solution for given equation is x = 3.
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