Applying precedence of operations, the parenthesis on the operations are inserted as follows:
(6+9)/3+(16-4)*236/(4 + 2) - 4.(5-3)*2 + 8*(5 - 2).What is the precedence of operations?The acronym PEMDAS defines the precedence of operations, from highest to lowest, as follows:
P: Parentheses.E: Exponent.M: Multiplication.D: Division. (same precedence as multiplication).A: Addition.S: Subtraction. (same precedence as addition).For the first item, we want a result of 29, hence the expression will be of:
(6+9)/3+(16-4)*2.
As the equivalent result will be of:
(6+9)/3+(16-4)*2 = 15/3 + 12 x 2 = 5 + 24 = 29.
For the second item, we want a result of 2, hence the expression will be of:
36/(4 + 2) - 4.
As the equivalent result will be of:
36/6 - 4 = 6 - 4 = 2.
For the third item, we want a result of 28, hence the expression will be of:
(5-3)*2 + 8*(5 - 2)
As the equivalent result will be of:
(5-3)*2 + 8*(5 - 2) = 2 x 2 + 8 x 3 = 4 + 24 = 28.
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A citizen wants to propose to the city council extending the hours at the local public library on some weekdays. To measure support for extended hours, the citizen visits neighborhood homes and asks adults the following: "Would you agree that the closing time of the library should be extended by one hour on weekdays to accommodate working families?” Of the 212 adults surveyed, 86% agreed with the statement. Which of the following statements about the results is true?
(A)The 86% support provides substantial evidence that the library hours should be extended.
(B)More families should be asked the same question to be sure of community support.
(C)The survey suffers from question wording bias and may not represent true support for the extended hours.
(D)The survey suffers from voluntary response bias and may not estimate true support for the extended hours
The true statement about the result is that D. The survey suffers from voluntary response bias and may not estimate true support for the extended hours
How to illustrate the information?From the information, in order to measure support for extended hours, the citizen visits neighborhood homes and asks adults the research question.
This illustrates bias as the citizen wants to propose to the city council extending the hours at the local public library on some weekdays.
Therefore, the true support may not be illustrated. In conclusion, the correct option is D.
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Please help with finding the approximate mean pretty easy 7th grade math.
Use the Chain Rule to find ∂z/∂s and ∂z/∂t. (Enter your answer only in terms of s and t. Please use * for multiplication between all factors.)[tex]z = x^{7}y^{7}, x = s cos(t), y = s sin(t)[/tex]
Applying the Chain Rule, the derivatives are given as follows:
[tex]\frac{\partial z}{\partial s} = 7(s\cos{t})^6(s\sin(t))^6(y\cos{t} + x\sin{t})[/tex][tex]\frac{\partial z}{\partial t} = 7s(s\cos{t})^6(s\sin{t})^6(-y\sin{t} + x\cos{t})[/tex]What is the derivative of Z as a function of s?
The function Z is defined as follows:
z = x^7y^7.
The variables x and y are functions of variables s and t, as follows:
x = s cos(t).y = s sin(t).Hence the derivative of z as a function of s is given as follows:
∂z/∂s = (dz/dx)(dx/ds) + (dz/dy)(dy/ds).
Hence, applying the derivative rules for the exponents, and for the exponents, we have that:
[tex]\frac{\partial z}{\partial s} = 7x^6y^7\cos{(t)} + 7y^6x^7\sin{(t)} = 7x^6y^6(y\cos{t} + x\sin{t})[/tex]
Replacing the values of x and y, we have that:
[tex]\frac{\partial z}{\partial s} = 7(s\cos{t})^6(s\sin(t))^6(y\cos{t} + x\sin{t})[/tex]
What is the derivative of Z as a function of t?We follow the same logic as above, only that now the inside derivatives, that is, the derivatives of x and y, are as function of t and not of s, hence:
∂z/∂t = (dz/dx)(dx/dt) + (dz/dy)(dy/dt).
Then:
[tex]\frac{\partial z}{\partial t} = -7x^6y^7s\sin{(t)} + 7y^6x^7s\cos{(t)} = 7sx^6y^6(-y\sin{t} + x\cos{t})[/tex]
Then, replacing x and y as functions of s and t, we have that:
[tex]\frac{\partial z}{\partial t} = -7x^6y^7s\sin{(t)} + 7y^6x^7s\cos{(t)} = 7s(s\cos{t})^6(s\sin{t})^6(-y\sin{t} + x\cos{t})[/tex]
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use left and right endpoints and the given number of rectangles to find two approximations of the area of the region between the graph of the function and the x-axis over the given interval.
The two approximations of the region's area between the graph of the function and the x-axis over the given interval are 14.31 < AREA < 17.01
We have :
f(x) = 9 -x [ 2, 4 ], 6 rectangles.
Here, a = 2 and b = 4 , n = 6
The width of the rectangles will be
x' = [tex]\frac{b-a}{n}[/tex]
x' = [tex]\frac{4-2}{6} = \frac{2}{6} = \frac{1}{3} = 0.33[/tex]
Now, The given function is f(x) = 9 -x
[tex]f(x_{i}) = x_{i} - 9[/tex]
For [tex]x_{0} = 0[/tex], [tex]f(x_{0} ) = 9[/tex]
For [tex]x_{1} = 0.3[/tex], [tex]f(x_{1} ) = 9 -0.3 = 8.7[/tex]
For [tex]x_{2} = 0.6[/tex], [tex]f(x_{2} ) = 9 -0.6 = 8.4[/tex]
For [tex]x_{3} = 0.9[/tex], [tex]f(x_{3} ) = 9 -0.9 = 8.1[/tex]
For [tex]x_{4} = 1.2[/tex], [tex]f(x_{4} ) = 9 -1.2 = 7.8[/tex]
For [tex]x_{5} = 1.5[/tex], [tex]f(x_{3} ) = 9 -1.5 = 7.5[/tex]
For [tex]x_{6} = 2.1[/tex], [tex]f(x_{3} ) = 9 -2.1 = 7.2[/tex]
Now, The area by using an approximation using 6 approximating rectangles and right endpoints is given by.
A = Sum of [tex]f_{i}x'[/tex] = [tex](f_{1} + f_{2} + f_{3} + f_{4} + f_{5} + f_{6})x'\\[/tex]
A = (8.7 + 8.4 + 8.1 + 7.8 + 7.5 + 7.2)*0.3
A = 47.7*0.3 = 14.31
The area by using an approximation using 6 approximating rectangles and left endpoints is given by:
A = Sum of [tex]f_{i}x'[/tex] = [tex](f_{0} + f_{1} + f_{2} + f_{3} + f_{4} + f_{5} + f_{6} } )x'\\[/tex]
A = (9+8.7 + 8.4 + 8.1 + 7.8 + 7.5 + 7.2)*0.3
A = 17.01
Thus 14.31 < AREA < 17.01
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El volumen de un cubo que tiene como arista 14 cm es?
1000 cm3
2.744 cm3
216 cm3
The volume of the cube is 2744 cm³.
QuadrilateralsThere are different quadrilaterals, for example: square, rectangle, rhombus, trapezoid and parallelogram. Each type is defined accordingly to its length of sides and angles. For example, in a square all angles are 90° and all sides present the same value.
A square is a 2D figure, when the square is associated a 3D figure, the figure is called a cube. The cube presents 6 faces with length (l) , height (h) and width (w) equal. Thus, the cube presents congruent edges.
The volume is given from the formula V=a³, where a is a congruent edge.
The question gives:
edge=14 cmTherefore,
V=a³
V=14³
V=14*14*14
V=2744 cm³
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Represent the system with a matrix.
2x+3y+5z=9
-x+4z=10
-6x+z-12=y
The given system of equations represented as a matrix is
[tex]\left[\begin{array}{ccc}2&3&5\\-1&0&4\\-6&-1&1\end{array}\right] \left[\begin{array}{c}x\\y\\z\end{array}\right] = \left[\begin{array}{c}9\\10\\12\end{array}\right][/tex]
Representing system of linear equations with a matrixFrom the question, we are to represent the given system of linear equations with a matrix.
The given system of equations is
2x + 3y + 5z = 9
-x + 4z = 10
-6x + z -12 = y
First, we will write the third equation in standard form
-6x + z -12 = y
This becomes
-6x - y + z = 12
Thus,
The system of equations becomes
2x + 3y + 5z = 9
-x + 4z = 10
-6x - y + z = 12
Thus,
The system of equations can be written as a matrix as shown below
[tex]\left[\begin{array}{ccc}2&3&5\\-1&0&4\\-6&-1&1\end{array}\right] \left[\begin{array}{c}x\\y\\z\end{array}\right] = \left[\begin{array}{c}9\\10\\12\end{array}\right][/tex]
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please help see picture above^^ thank you
From the calculations, we could obtain the maximum speed of the car as 72.6 miles/hr.
What is proportionality?The term proportionality gives us an idea of the nature of the relationship that does exist between the variables in a given situation. The proportionality could be;
1) Direct
2) Inverse
3) Joint
Given that the stopping distance (D) varies directly as the speed (S), we could say;
D α S
Introducing the constant k
D = kS
k = D/S
k = 0.027 miles/40 mile/hr
k = 6.75 * 10^-4 hours
Maximum speed = D/k
= 0.049 miles/ 6.75 * 10^-4 hours
= 72.6 miles/hr
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Please help with number 8 step by step
Answer:
It is a function because circles are functions
Step-by-step explanation:
the formula for a circle is
[tex](x-h)^2+(y-k)^2=r^2[/tex]
(h,k) = center
r=radius
radius is 4 because diameter is 8
Center is (2,1)
plug it into the equation:
[tex](x-2)^2+(y-1)^2=16[/tex]
Solve for x. 9 + x/2=14 x=
If 6times a number is added to -3, then the results is equal to 9 times the number. Find the number
To determine the missing number:
[tex]\text{Let the missing number = x}[/tex][tex]\begin{gathered} 6\text{ times a number = 6x} \\ 6x+(-3)=9x \\ 6x-3=9x \end{gathered}[/tex]collect like terms
[tex]\begin{gathered} 6x-9x=3 \\ -3x=3 \\ \text{divide both side by -3} \\ -\frac{3x}{-3}=\frac{3}{-3} \\ x=-1 \end{gathered}[/tex]Therefore the missing number = -1
Every month, Omar buys baskets of wings to serve at a party for his friends. In May, he bought three more than twice the number of baskets of wings he bought in April. If Omar bought 15 baskets of wings in May, how many did he buy in April?
*Use distributive property*
Answer:
33
Step-by-step explanation:
24 and 27 are vertical angles.
Select Choice the angles are Select Choice and are formed by two Select Choice lines.
Yes/no
Adjacent/non adjacent
Parallel/intersecting
Yes they are vertical angles, the angles are nonadjacent and are formed by intersecting lines.
What are Vertical Angles?When two lines that are straight intersect with each other, they form two pairs of opposite angles that are called vertical angles.
Vertical angles share a common vertex both no common sides and are therefore referred to as non-adjacent angles.
Thus, the image shows that lines intersect to form angle 4 and angle 7.
Angle 4 and angle 7 share a common vertex but do not share a common side, hence they are nonadjacent to each other, as shown in the diagram.
We can conclude that they are vertical angles because they are nonadjacent and are formed by intersecting lines.
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The elevation of Desert Shores, California, is less that -55 meters. Which of the following best describes Desert Shores.
A. Desert Shores is lower than 55 meters below sea level.
B. Desert Showers is lower that 55 meters above sea level
C. Desert Shores is higher than 55 meters below sea level.
D. Desert Shores is higher than 55 meters above sea level.
The option that best describes the elevation of Desert Shores is; A. Desert Shores is lower than 55 meters below sea level.
What is the Elevation below sea level?We are told that the elevation of Desert Shores, California, is less than -55 meters.
Now, an elevation of a natural landmass like this is usually given with reference to the sea level. If above sea level, it is positive but if below sea level, it is negative.
Now, the elevation is negative as we can see that it is given as -55 meters. Thus, we can easily conclude that Desert Shores is lower than 55 meters below sea level.
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20) A gas station charges $4.09 for a gallon of premium unleaded. The gas station charges
$.20 less per gallon of gasoline if a customer also gets a car wash. A car wash cost $10.
Write an inequality and solve to find the possible amounts (in gallons round to the nearest
hundredth) of gasoline that you can buy if you also get a car wash and can spend at most
$30?
He can buy $100 of gasoline that you can buy if you also get a car wash and can spend at most $30.
What is inequality?An inequality in mathematics is a relation that compares two numbers or other mathematical expressions in an unequal way. The majority of the time, size comparisons between two numbers on the number line are made. Different types of inequalities are represented by a variety of notations, including:
The symbol a b indicates that an is smaller than b.
When a > b is used, it indicates that an is bigger than b.
Given Data
The gas station charges $0.20 less per gallon of gasoline if a customer also gets a car wash. A car wash cost $10.
Inequality-
$0.2x + $10 = $30
0.2x = $20
x = 100
He can buy $100 of gasoline that you can buy if you also get a car wash and can spend at most $30.
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Right triangle DEF is shown below.What is DF to the nearest tenth of a meter?
Answer: 25.1º
Explanation
As the given triangle is a right triangle, we can use trigonometric functions to find DF, specifically:
[tex]\cos x=\frac{adjacent}{hypotenuse}[/tex]where the adjacent is the side adjacent to our angle and the hypotenuse is the longest side (side opposite to the 90º angle).
Based on this, we can replace the values as follows:
[tex]\cos(23\degree)=\frac{DF}{27.3}[/tex]Solving for DF:
[tex]DF=27.3\cdot\cos(23\degree)[/tex][tex]DF=27.3\cdot\cos(23\degree)[/tex][tex]DF\approx25.1[/tex]graph AgraphwebImaginary A3222Real342 3 4-123graphAe7in A22Reals+3212343a-44which graph depicts a complex number with as the imaginary partA graphOgraphCCgraph
Graph (D) shows a complex number with an imaginary component, i.
What is a graph?In mathematics, a graph is a visual representation or diagram that shows data or values in an ordered way. The relationships between two or more things are frequently represented by the points on a graph. Bar graphs, circle graphs, and line graphs are the three most frequently used types of graphs.Different types of data can be displayed using different types of graphs.So, we are aware that a complex number is shown as:
z= x+iyWhere x stands for a number's real value and y for a number's imaginary value.
Which stands for the point (x,y)As a result, the number I is written as:
z=0+1.iThis indicates that the symbol for the number I is a point (0,1).
Therefore, the number I has a value of 1 on the hypothetical axis.So, Graph D is the appropriate selection.Therefore, graph (D) shows a complex number with an imaginary component, i.
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The complete question is given below:
Which graph depicts a complex number with i as the imaginary part?
simplify the expression -1.1 + (-3.9). On the test, when tom simplified the expression he got -2.8. What mistake did tom likely make when he simplified the expression?
Answer:
the answer is -5.0
Step-by-step explanation:
Tom subtracted -1.1 from -3.9 instead of adding them together
Simplifying a Rational Expression Simplify (a ^ 2 * b ^ 8)/(a ^ 2 * b ^ 3 - a ^ 4 * b ^ 2); (a * b ^ 2)/(1 - a ^ 4 * b ^ 2); (a ^ 3 * b ^ 8)/(a ^ 2 * b ^ 2 * (b - a ^ 2)); b/(1 - a); (a * b ^ 4)/(b - a ^ 2)
Answer:
ab^4/b-a^2
Step-by-step explanation:
...........
2(64x² - 25) (x² + 49) = 0
Answer:
[tex]x=-7i, 7i, 5/8, -5/8[/tex]
Step-by-step explanation:
[tex](64x^2-25)(x^2+49)=0 \\ \\ (8x-5)(8x+5)(x+7i)(x-7i)=0 \\ \\ x=-7i, 7i, 5/8, -5/8[/tex]
I think I got this right is it right ?
Answer:
1. Correct
2. Incorrect
3. Correct
4. Correct
5. Incorrect
Step-by-step explanation:
For the ones you got wrong:
1 / (-3)² = 1/9
and
[tex]3^{-2}[/tex] = 1/9
Answer:
First one is correct
Second one is 1/9
Third one is -1/9
Fourth one is 1/9
Fifth one is 1/9
Step-by-step explanation:
Second one -
Use the rules of exponents to simplify the expression;To raise a power to another power multiply the exponents(-3)^2(-1)Multiply 2 times -1(-3)^2Raise -3 to the power of -2 1/9Third one - Calculate 3 to the power of -2 to get -1/9Fourth one - Calculate -3 to the power of -2 to get 1/9Fifth one - calculate 3 to the power of -2 to get
1/9
Please help I’ll mark you as brainliest if correct!
Answer:
21 Degrees.
Step-by-step explanation:
It was 22 degrees by noon, by then the temperature had already risen by
eight degrees, but since we are going back in time, we would subtract the eight degrees.
22 - 8 = 14.
Now we are at 9 A.M, it is 14 degrees. But, the temperature had doubled from 5-9 A.M, so we would divide our fourteen by two in order to half it.
14 ÷ 2 = 7.
Now we are at 5 A.M.
From midnight to 5 A.M the temperature dropped fourteen degrees so we would add that fourteen back into the equation.
7 + 14 = 21.
Hope this helped!!
Angle C is an acute angle with sec C = 9/4 and sin C =
√65/9. What are the values of cos C and csc C?
From trigonometric ratios we calculate the value of the cos C is 4/9 and the value of cosec C is 9/√65 .
Real functions known as trigonometric functions in mathematics connect right-angled triangle angles and the ratios of their two side lengths.
The terms trigonometric functions, circular functions, and angle functions are also used to describe them. Trigonometric functions are frequently employed in all fields of study involving geometry, including geodesy, solid mechanics, celestial mechanics, and many more. Given that one of the most fundamental periodic functions is the Fourier transform, it is frequently employed to examine periodic phenomena.Sine, cosine, and tangent are the three trigonometric functions that are employed in modern mathematics the most frequently. The less common cotangent, secant, and cosecant are their reciprocals. The hyperbolic functions and their corresponding inverse functions have analogues for each of these six trigonometric functions.We know that sec C = 1/cos C
Hence the value of cos C = 4/9 .
Again we know that the value of sin C=1/cosec c
Therefore the value of cosec C is 9/√65 .
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RS has endpoints R(-11, 10) and S(-6, -5). Point T divides RS such that ST:TR is 2:3.
What are the coordinates of T?
Write your answers as integers or decimals.
()
Check the picture below.
[tex]\textit{internal division of a line segment using ratios} \\\\\\ S(-6,-5)\qquad R(-11,10)\qquad \qquad \stackrel{\textit{ratio from S to R}}{2:3} \\\\\\ \cfrac{S\underline{T}}{\underline{T} R} = \cfrac{2}{3}\implies \cfrac{S}{R} = \cfrac{2}{3}\implies 3S=2R\implies 3(-6,-5)=2(-11,10)[/tex]
[tex](\stackrel{x}{-18}~~,~~ \stackrel{y}{-15})=(\stackrel{x}{-22}~~,~~ \stackrel{y}{20}) \implies T=\underset{\textit{sum of the ratios}}{\left( \cfrac{\stackrel{\textit{sum of x's}}{-18 -22}}{2+3}~~,~~\cfrac{\stackrel{\textit{sum of y's}}{-15 +20}}{2+3} \right)} \\\\\\ T=\left( \cfrac{ -40 }{ 5 }~~,~~\cfrac{ 5}{ 5 } \right)\implies {\Large \begin{array}{llll} T=(-8~~,~~1) \end{array}}[/tex]
The Omicron Model 99 television costs $450. During a special sale, it’s marked 1⁄3 off. How much money will you save buying this TV on sale?
Answer:
225
Step-by-step explanation:
if it is 1/3 off, then it means it's at 2/3 the price. now, you have to divide 450/2 to get the answer. 2/3 divided by 2=1/3
450/2=225, and thats how much money you will save
WELL GIVE U BRAINLIEST ASAP
Drag the numbers to order them from least to greatest.
Answer:
3/5 is the smallest, 7/9 is in the middle and 5/6 is the biggest
Step-by-step explanation:
Brainlest, Please!
Answer: 3/5 is first, 7/9 is second, and 5/6 is last.
Ver en españolWhat is the area?5 in5 in square inches
From the question, we are asked to find the area.
Since all the sides of the figure are the same, then it is a square.
So we will be using the area of a square formula to solve it.
Formula for area of a square is:
Area = a x a = a²
a = 5 in
So,
Area = 5 x 5 = 5² = 25
Therefore, the area of the square is 25 in²
2/3 ÷ 4/9 What is the answer.
Answer:
3/2Step-by-step explanation:
2/3 ÷ 4/9 What is the answer?
2/3 : 4/9 =
2/3 * 9/4 =
3/2
Mariam wants to buy strawberries and apples to
make a fruit tart. Strawberries cost $3 per pound
and apples cost $3.25 per pound. How many pounds
of fruit does she buy if she buys 0.5 pounds of
strawberries and 3 pounds of apples? How many
pounds of fruit does she buy if she buys x pounds of
strawberries and y pounds of apples?
Answer:
Answer bellow with explanations
Step-by-step explanation:
if Miriam buys 0.5 pounds of strawberries and 3 pounds of apples she will in total would have bought 3.5 pounds of fruit.
if you are looking for the price she had to pay for the fruits above the equation to solve that is as following.
0.5 x 3$ = 1.5$
3.0 x 3.25 = 9.75$
total for the fruits needed above would be 1.5$ + 9.75$ = 11.25$
if you are looking for the amount of pounds converted into the amount of fruit
0.5/3$ = 0.16(6) pounds of strawberries
3/3.25$= 0.92307692307 pounds of apples
total of pounds of fruit that have been purchased is equal to 0.16(6) + 0.92307692307 = 1.08974358973 pounds
If Miriam buys x pounds of strawberries and y pounds of apples
it can be shown in an equation using 2 unknown values
X(strawberries)
Y(apples)
x/3$ + y/3.25$
to calculate the amount of pounds that have been purchased
A line passes through the points (7, 10) and (7, 20). What is true about the slope of the line? *
The slope of the line is indefinite (∞). Also, the line will be parallel to the x-axis.
It is given in the question that a line passes through the points (7, 10) and (7, 20).
We have to find the slope of the line.
We know that,
Slope of a line with coordinates (a,b) and (c,d) is given by:-
(d - b)/( c - a)
Here,
a = 7,
b = 10,
c = 7 and,
d = 20
Hence, we can write,
Slope of the line = (20 - 10)/( 7 - 7) = 10/0 = ∞.
Hence, the slope of the line is indefinite.
Here, as the x -coordinate of both the points are same, this line will be parallel to the x - axis.
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Please help I’ll mark you as brainliest if correct!
The value of a, b, c and d are 25, 3, 14 and 7 such that the sum of all rows, columns and diagonals are 48.
Given to us a magic square in which the sum of all rows, columns and diagonals are same. Then, we have to complete the missing numbers i.e., a, b, c and d respectively.
Let's proceed to solve this magic square accordingly.
First let's calculate that what will be the sum of all rows, columns and diagonals.
From the figure of magic square one diagonal is completely filled from that we can easily calculate the sum of the diagonals.
Sum = 5+16+27 = 48
Then, we can find the value of a, b, c and d easily.
5+a+18 = 48
23+a = 48
a = 48-23
a = 25
Therefore, the value of a is 25.
29+16+b = 48
45+b = 48
b = 48-45
b = 3
Therefore, the value of b is 3.
Now, 5+29+c = 48
34+b = 48
c = 48-34
c = 14
Therefore, the value of c is 14.
Then, we have
c+d+27 = 48
14+d+27 = 48
41+d = 48
d = 48-41
d = 7
Therefore, the value of d is 7.
Hence, we have completed the magic square in which the sum of all rows, columns and diagonals are 48.
Therefore, the value of a, b, c and d are 25, 3, 14 and 7 respectively.
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