9514 1404 393
Answer:
x^2/81 -y^2/19 = 2500
Step-by-step explanation:
The time difference between signals is 3 µs, so the distance difference is ...
(300 m/µs)(3 µs) = 900 m
If we assume the coordinates of Q are (-500, 0), then the distances from point X to the control towers are ...
XQ = √((x +500)^2 +y^2)
XR = √((x -500)^2 +y^2)
We want the difference in distances to be 900, so we have the equation ...
|XQ -XR| = |√((x +500)^2 +y^2) -√((x -500)^2 +y^2)| = 900
Squaring both sides gives ...
(x +500)^2 +2(x +500)y +y^2 -2√(((x +500)^2 +y^2)((x -500)^2 +y^2)) +((x -500)^2 +y^2) = 810000
Separating the root from the rest of the equation, squaring again, and simplifying the rather messy expression, we can arrive at the equation ...
x^2/81 -y^2/19 = 2500 . . . . . a hyperbola opening horizontally
Eddie is paid $17.25 per hour for a regular 37-hour week. His overtime rate is 1 times his regular hourly
rate. Use his time card above to find his total pay for the week.
Answer:
$638.25
Step-by-step explanation:
I multiplied 17.25 times 37. The product was $638.25.
I was a bit confused when it said,"His overtime rate is 1 times his regular hourly rate." Since it is 1 times his hourly rate, it shouldn't affect the answer.
Your friend was bored one day and started making patterns using Cheerios from a new box he had opened. He laid the Cheerios on the table as such:
Based on the two images above and the information about the box, answer the following questions.
A) Identify and label the variable
B) Make a table for up to 8-figure patterns
C) Write an equation to represent the nth term of the sequence.
D) If the pattern continues, what figure number will have 20 whole Cheerios in it?
E) Is it reasonable to think this pattern would continue forever? If not, explain.
F) Based on the information provided, what is the largest figure number we can have using a full box of Cheerios?
PLS ANSWER ALL OF THE QUESTIONSSS I REALLY NEED THE ANSWERS ASAPPPPPPP PLEASE AND THANK YOU
A) The variable is n, which represents the number of the figure in the pattern.
B) Here is a table for up to 8-figure patterns:
Figure Number of Cheerios
1 1
2 3
3 6
4 10
5 15
6 21
7 28
8 36
C) The equation to represent the nth term of the sequence is n(n+1)/2.
D) If the pattern continues, the figure number that will have 20 whole Cheerios in it is 12.
E) It is not reasonable to think this pattern would continue forever. The number of Cheerios in each figure is increasing by 2 each time. This means that the number of Cheerios in the figure will eventually exceed the number of Cheerios in a box.
F) Based on the information provided, the largest figure number we can have using a full box of Cheerios is 107. This is because there are 108 Cheerios in a box, and the number of Cheerios in each figure is increasing by 2 each time.
Here is a more detailed explanation of how to answer each question:
A) Identify and label the variable
The variable is n, which represents the number of the figure in the pattern. For example, the first figure is figure 1, the second figure is figure 2, and so on.
B) Make a table for up to 8-figure patterns
Here is a table for up to 8-figure patterns:
Figure Number of Cheerios
1 1
2 3
3 6
4 10
5 15
6 21
7 28
8 36
C) Write an equation to represent the nth term of the sequence
The equation to represent the nth term of the sequence is n(n+1)/2. This equation can be derived by looking at the table of values. For example, the number of Cheerios in the first figure is 1, which is equal to 1(1+1)/2. The number of Cheerios in the second figure is 3, which is equal to 2(2+1)/2. And so on.
D) If the pattern continues, what figure number will have 20 whole Cheerios in it?
If the pattern continues, the figure number that will have 20 whole Cheerios in it is 12. This can be found by solving the equation n(n+1)/2 = 20. The solution is n = 12.
E) Is it reasonable to think this pattern would continue forever? If not, explain.
It is not reasonable to think this pattern would continue forever. The number of Cheerios in each figure is increasing by 2 each time. This means that the number of Cheerios in the figure will eventually exceed the number of Cheerios in a box.
F) Based on the information provided, what is the largest figure number we can have using a full box of Cheerios?
Based on the information provided, the largest figure number we can have using a full box of Cheerios is 107. This is because there are 108 Cheerios in a box, and the number of Cheerios in each figure is increasing by 2 each time.
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a bus travels 1 1/2 hours for 80km.How many hours does it take to travel 4000km.
The number of hours it will take to travel 4000 km is 75 hours.
What is an expression?An expression is a way of writing a statement with more than two variables or numbers with operations such as addition, subtraction, multiplication, and division.
Example: 2 + 3x + 4y = 7 is an expression.
We have,
A bus travels 1 1/2 hours for 80km.
This can be written as,
1(1/2) hours = 80 km
3/2 hours = 80 km
Multiply 50 on both sides.
50 x 3/2 hours = 4000 km
75 hours = 4000 km
Thus,
It will take 75 hours to travel 4000 km.
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y is directly proportional to x and k is a constant. Which equation
shows this?
y = x +k
y = kx
y = k/x
y = x-k
Answer:
y = kx
Step-by-step explantion:
We did this in math class and I know it is right! I hope this helps you! :)
1. Expected value and Bivariate Probability. The Chamber of Commerce of a Canadian city
has conducted an evaluation of 300 restaurants in its metropolitan area. Each restaurant received
a rating of 1-3 on its meal price (1 = least expensive; 3 = most expensive), and quality (1 =
lowest quality; 3 = greatest quality). Below is a crosstabulation of the rating data.
Meal Price (y)
Quality (x) 1 2 3 Total
1 42 39 3 84
2 33 63 54 150
3 3 15 48 66
Total 78 117 105 300
a. Develop a bivariate probability distribution for quality and meal price of a randomly selected
restaurant in this Canadian city. Let x = quality rating and y = meal price.
b. Compute the expected value for quality rating, x.
c. Compute the expected value for meal price, y.
d. The Var(x+y) = 1.6691. The Var(x) = 0.4964. The Var(y) = 0.6019. Compute the covariance
of x and y. What can you say about the relationship between quality and meal price. Is this what
you would expect?
e. Compute the correlation coefficient between quality and meal price. What is the strength of
the relationship? Do you suppose it is likely to find a low-cost restaurant in the city that is also
high quality? Why or why not?
a) Let x denote the quality rating and y denote the meal price.
b. From the above table, the marginal density function of x is 1.94
c. From the probability table, the marginal density function of y is 2.09
What is the Probability Distribution Table?The probability distribution table for quality and meal price is obtained by dividing each and every frequency by the total frequency of 300 is attached in the image.
The probability distribution is obtained in the attached image below.
The expected value of x is,
1 x 0.28 + 2 x 0.50 + 3 x 0.22
= 1.94
To find the marginal density function of y
1 x 0.26 + 2 x 0.39 + 3 x 0.35
= 2.09
Given that var(x+y)=1.6691
var(x)=0.4964 and var(y)=0.6019
var(x+y) =1.6691
var(x) + var(y) +2* cov(x,y)=1.6691
0.4964+0.6019+ 2 *cov(x,y) =1.6691
1.0983+ 2 * cov(x,y) =1.6691
2 * cov(x,y) =1.6691-1.0983
2* cov(x,y)=0.5708
cov(x,y) =(0.5708)/2
cov(x,y)= 0.2854
Thus, the covariance of x and y is, 0.2854.
Here, the covariance of x and y is positive.
Thus, the relationship between quality and meal price is positive.
If the quality of the meal increases then the meal price also increases.
Yes, the expected result is positive because if the quality of the meal is good then meal price increases.
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Simplify to a single trig function with no fractions.
Answer:
sin(t)
Step-by-step explanation:
tan(t)/sec(t) = tan(t) * 1/sec(t) = sin(t)/cos(t) * cos(t) = sin(t)
a A local pizza shop has a membership program for frequent buyers. The membership costs $25 per month and members get a discounted price of $1.75 per slice of pizza. Isaac purchased a membership to this pizza shop. How much would Isaac have to pay the pizza shop if he bought 5 slices of pizza this month? What would be the monthly cost for x slices of pizza?
Answer:
$33.75; 25+1.75x
Step-by-step explanation:
a) cost = membership fee + cost of pizzas
= 25 + 1.75*5
= 25 + 8.75
= ($) 33.75
b) cost = 25 + 1.75x
Find the slope and y-intercept of the line.
y=7/4x-10
Answer
-10;7/4
Answer:
The slope is 7/4 and the y intercept is -10
Step-by-step explanation:
y=7/4x-10
This equation is written is slope intercept form
y = mx+b where m is the slope and b is the y intercept
The slope is 7/4 and the y intercept is -10
It is estimated that only 68% of drivers wear their safety belt.
Part A: What is the probability that exactly 3 drivers are wearing their safety belts if a police officer pulls over five drivers? (5 points)
Part B: What is the probability the next driver wearing their safety belt that the police officer pulls over is the fifth driver? (5 points)
Step-by-step explanation:
we have 2 probabilities :
1. that a driver is wearing their safety belts : 0.68
2. that the driver is NOT wearing the safety belts :
1-0.68 = 0.32
A.
3 drivers are wearing it, 2 are not is a combination of
0.68³×0.32²
and how many combinations of these 5 probabilities can we have (e.g. the first 3 are wearing them, or the last 3 are wearing them, or ...) ?
that is 5 over 3 combinations :
5! / (3! × (5-3)!) = 5! / (3! × 2!) = 5×4/2 = 5×2 = 10
so, we have
10×0.68³×0.32² = 0.321978368
B
I am not sure I understand the question.
I assume this means from the 5 drivers they pull over the first 4 don't wear the seat belts, and only the fifth does.
so that is then
0.32⁴×0.68
and only one combination is possible. so, the result is just the product of these probabilities :
0.32⁴×0.68 = 0.0071303168
how do I solve this linear equations by substitution x=5 x + y = 4
Substitute 5 for x in the equation x+y=4 to obtain the value of y.
\(\begin{gathered} 5+y=4 \\ y=4-5 \\ =-1 \end{gathered}\)So solution of the equations is (5,-1).
The question is attached. I need help with this question
Given the equation of a quadratic function in the form:
\(y=ax^2+bx+c\)Equation: y = x² - 6x + 7
where a = 1, b = -6, and c = 7.
Vertex form of a quadratic function:
\(y=a\left(x-h\right)^2+k\)where (h, k) is the vertex.
To find (h, k):
\(\begin{gathered} h=\frac{-b}{2a} \\ \\ h=\frac{6}{2} \\ \\ h=3 \end{gathered}\)\(\begin{gathered} k=f(3) \\ k=3²-6(3)+7 \\ k=-2 \end{gathered}\)Vertex = (3, -2)
ANSWER
Vertex form of the quadratic equation:
\(y=(x-3)^2-2\)Which figure can be formed from the net?
__________________________________
(Reporting any spams/wrong answers)
(Giving brainliest to correct answer)
___________________________
Answer:
C
Step-by-step explanation:
For these types of problems, its important that we focus on the base as well as the lengths of the base and any other given lengths.
Here, the net has a base that forms a square with side lengths of 8mm.
So automatically, we can eliminate choices a and d as both have a base that is a triangle rather than a square.
We've also noticed that the base has a length of 8mm
If we look at B and C closely, we can tell that B has base lengths of 10mm while C has base lengths of 8mm.
So C is the correct answer choice.
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The senior classes at Snellville High and General High planned separate trips to the water park. The senior class at Snellville rented and filled 12 vans and 14 buses with 796 students. General High rented and filled 14 vans and 12 buses with 738 students. How many students would fill 2 buses and 3 vans?
Answer:
133 Students
Step-by-step explanation:
Let the number of student in a van=v
Let the number of student in a bus=b
The senior class at Snellville rented and filled 12 vans and 14 buses with 796 students.
Therefore: 12v+14b=796
General High rented and filled 14 vans and 12 buses with 738 students.
Therefore: 14v+12b=738
We solve the two resulting equations simultaneously
12v+14b=796
14v+12b=738
Multiply equation 1 by 12 and equation 2 by 14 to eliminate b
144v+168b=9552
196v+168b=10332
Subtract
-52v=-780
Divide both sides by -52
v=15
We substitute v=15 to obtain b in any of the equations
12v+14b=796
12(15)+14b=796
14b=796-180
14b=616
Divide both sides by 14
b=44
Therefore a bus contains 44 Students and a Van contains 15 students.
Number of Students who would fill 2 buses and 3 vans
=2b+3v
=2(44)+3(15)
=133 Students
2 Write 386 in expanded form
Answer:
300+ 80+6
Step-by-step explanation:
i think i not sure
You need 45 mL of an 8% Boric acid solution for an experiment in your chemistry class. You have bottles of 5% Boric acid and 15% Boric acid to mix together. How many ml of each solution should you mix together?
The solution is
The amount of 5 % Boric acid solution is = 31.5 mL
The amount of 15 % Boric acid solution is = 13.5 mL
What is an Equation?
Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
Given data ,
Let the amount of 5 % Boric acid solution needed for the mix = x
Let the amount of 15 % Boric acid solution needed for the mix = y
Now , the total amount of solution is = 45 mL
So , the equation will be
x + y = 45 be equation (1)
And the mix is 60 milliliters of a 3 % Boric acid solution
So , the equation will be
The Boric acid in x + the Boric acid in y = 8 % of 45
Substituting the values in the equation , we get
0.05x + 0.15y = 0.08 x 45
On simplifying the equation , we get
0.05x + 0.15y = 3.6
Multiply by 100 on both sides of the equation , we get
5x + 15y = 360 be equation (2)
Multiply equation (1) by 5 , we get
5x + 5y = 225 be equation (3)
Subtracting equation (3) from equation (2) , we get
10y = 360 - 225
10y = 135
Divide by 10 on both sides of the equation , we get
y = 13.5 mL
Substitute the value of y in equation (1) , we get
x + y = 45
x + 13.5 = 45
Subtracting 13.5 on both sides of the equation , we get
x = 31.5 mL
Hence , the amount of 5 % Boric acid solution needed is 31.5 mL and the amount of 15 % Boric acid solution needed is 13.5 mL
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Hi can any one teach me this constant difference
The constant differences between the consecutive terms are 2 (a); 2 (b), -3 (c), 7 (d), 1(e), and 6(f).
How do you find the constant difference in a sequence of numbers?In math, the constant difference can be defined as the number that defines the pattern of a sequence of numbers. This means that number that should be added or subtracted to continue with the sequence.
Due to this, to determine the constant difference it is important to observe the pattern and find out the number that should be added. For example, if the sequence is 2, 4, 6, 8, there is a difference of 2 between each of the numbers and this is the constant difference.
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The Center for Disease Control and Prevention estimates the number of persons aged 13 and older living with HIV is 1.1 million. Assume the US population aged 13 and older is 300 million. The test for HIV has an accuracy rate of 97%. Use this information to complete a table of possibilities and answer the question below.
If someone tests positive for HIV, what is probability they don't actually have HIV?
(Express your answer rounded correctly to the nearest tenth of a percent!)
The probability that someone who tests positive for HIV does not actually have HIV is 89.3% rounded to the nearest tenth of a percent.
what is percentage ?
Percentage is a way of expressing a number as a fraction of 100. The term "percent" means "per hundred", so when we say "50 percent", we mean 50 out of 100, or 50/100. Percentages are often used to represent ratios and proportions in everyday life and in many fields of study, including mathematics, science, economics, and finance.
To convert a fraction or decimal to a percentage, we multiply it by 100. For example, 0.75 is equivalent to 75 percent, because 0.75 times 100 equals 75. Conversely, to convert a percentage to a fraction or decimal, we divide it by 100. For example, 50 percent is equivalent to 0.5 or 1/2, because 50 divided by 100 equals 0.5.
According to the question:
Based on the information provided, we can create the following table of possibilities:
Actual HIV Status HIV Positive HIV Negative
Infected (1.1 million) 1.07M 0.03M
Not Infected (298.9 million) 8.97M 290.93M
From this table, we can see that of the 1.1 million people living with HIV, 97% will test positive for HIV, which is 1.07 million people. The remaining 3% will test negative, which is 0.03 million people.
Of the 298.9 million people not living with HIV, 97% will test negative for HIV, which is 290.93 million people. The remaining 3% will test positive, which is 8.97 million people.
So, out of the total population of 300 million people, 1.07 million will test positive for HIV, but only 1.07/(1.07+8.97) = 10.7% of them actually have HIV. Therefore, if someone tests positive for HIV, the probability they don't actually have HIV is 100% - 10.7% = 89.3%.
Therefore, the probability that someone who tests positive for HIV does not actually have HIV is 89.3% rounded to the nearest tenth of a percent.
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Triangle ABC was dilated using the rule DO,4. Triangle A'B'C' is the result of the dilation.
Point O is the center of dilation. Triangle A B C is dilated to create triangle A prime B prime C prime. The length of O B is three-fourths.
What is OB'?
1.5 units
3 units
4.5 units
6 units
Mark this and return
Answer:
(b) 3 units
Step-by-step explanation:
You want to know the length of OB' when OB = 3/4 and ∆ABC is dilated about point O by a factor of 4.
DilationThe dilation factor multiplies every length.
If OB is 3/4, then OB' is 4(3/4) = 3.
The length of OB' is 3 units.
<95141404393>
Look at this table, X W 11 1 10 3 13 -17 17 Is this relation a function? yes or no
[ it's a fraction but i can't write it as such. ]
Solve for M.
m/5 = 4
9
20
-9
-20
Answer:
the value of m will be 20
Givenf(x) = x^2 + 12x + 27.What function shows function fwritten in vertex form?
EXPLANATION
Given the function f(x) = x^2 + 12x + 27
The expression in vertex form is as follows:
\(f(x)=a(x-h)^2+k\)where a is the leading coefficient --> a=1
We need to compute h and k wich are the coordinates of the vertex (h,k)
The coordinates of the vertex are given by the following expression:
\(x_{\text{vertex}}=\frac{-b}{2a}\)where b=12:
\(x_v=\frac{-12}{2}=-6\)As x_v=-6 the expression of the function in standard form would be:
\(f(x)=(x-(-6))^2+k\)Removing the parentheses:
\(f(x)=(x+6)^2+k\)The only option that display this vertex form is the second one, hence that is the solution:
\(f(x)=(x-6)^2-9\)Sarah baked 560 apple pies and chicken pies. She sold 60% of the apple pies and 25% of the chicken pies. She sold exactly 1/2 of the pies altogether. How many apple pies did she bake?
Answer:
400 apple pies
Step-by-step explanation:
To solve for the number of apple pies baked by her, let's solve using equations and solving them by substitution method.
\(\textcolor{steelblue}{\text{\textcircled{1} Define the variables}}\)
Let the number of apple pies and chicken pies baked be a and c pies respectively.
\(\textcolor{steelblue}{\text{\textcircled{2} Form equations}}\)
Total pies baked= 560
a +c= 560 -----(1)
Total pies sold= ½(560)
\( \frac{60}{100} \text{a} \: + \frac{25}{100} \text{b} = 280\)
0.6a +0.25b= 280 -----(2)
\(\textcolor{steelblue}{\text{\textcircled{3} Solve by substitution}}\)
Since we are only interested in the value of a, we should eliminate the term c by making c the subject of equation. This ensures that after substitution, the equation will be in terms of a only.
From (1):
c= 560 -a -----(3)
Substitute (3) into (2):
0.6a +0.25(560 -a)= 280
Expand:
0.6a +140 -0.25a= 280
Simplify:
0.35a +140= 280
0.35a= 280 -140
0.35a= 140
Divide both sides by 0.35:
a= 140 ÷0.35
a= 400
\(\textcolor{steelblue}{\text{\textcircled{4} Concluding statement}}\)
Thus, she baked 400 apple pies.
-1/3 = r - 3/4 What is r?
Answer:
r = 5/12
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightEquality Properties
Multiplication Property of EqualityDivision Property of EqualityAddition Property of EqualitySubtraction Property of EqualityStep-by-step explanation:
Step 1: Define
-1/3 = r - 3/4
Step 2: Solve for r
[Addition Property of Equality] Add 3/4 on both sides: 5/12 = rRewrite: r = 5/12Here is a system of linear equations: Which would be more helpful for solving the system: adding the two equations or subtracting one from the other? Explain your reasoning. Solve the system without graphing. Show your work.
Okay, here we have this:
Considering the provided system we obtain the following:
The option more helpful for solving the system is add one equation to the other because in this way we can cancel the term of the "y", if we solve the system we obtain the following:
\(\begin{bmatrix}2x+\frac{1}{2}y=7 \\ 6x-\frac{1}{2}y=5\end{bmatrix}\)Adding the equations:
\(\begin{gathered} 8x=12 \\ x=\frac{12}{8} \\ x=\frac{3}{2} \end{gathered}\)Now, let's replacing in the first equation with x=3/2:
\(\begin{gathered} 2(\frac{3}{2})+\frac{1}{2}y=7 \\ 3+\frac{1}{2}y=7 \\ \frac{y}{2}=4 \\ y=8 \end{gathered}\)Finally we obtain that the solution to the system is x=3/2 and y=8.
A gym member tracked his weight. In the first week he gained 2 pounds. In the second week, he lost 5. In the third week, he lost 2 more. What was his overall change in weight?
This needs to be Divided
The remainder from the division of the polynomial (13 + 21y + 10y²) ÷ (2y + 3) is 4
What is the division of a polynomialThe division of a polynomial is typically denoted using the symbol " / " or the "long division" symbol. For example, to divide the polynomial f(x) by the polynomial g(x), we write:
f(x) / g(x)
The process of polynomial division involves finding the highest power of the divisor (g(x)) that can be multiplied by a term in the dividend (f(x)) to get a term that matches the highest power in the divisor. The resulting term is then subtracted from the dividend, and the process is repeated with the resulting polynomial until there is no remainder left.
The final result of polynomial division is the quotient polynomial, which consists of the coefficients of the terms that were successfully divided, and the remainder polynomial, which consists of any terms that could not be divided. The remainder is always of a lower degree than the divisor.
The division of the given polynomial is ;
(13 + 21y + 10y²) ÷ (2y + 3) = 5y + 3 + (4/2y + 3)
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Which of the following is the graph of 2x+3y=6
Taking point (0,-2) of graph one and replacing in the equation;
2x+3y=6
2(0)+3(-2)=6
-6=6
So graph isn't the required graph.
Taking point (0,2) of graph 2;
2x+3y=6
2(0)+3(2)=6
6=6
So, graph 2 is the required graph.
Answer:
nice
Step-by-step explanation:
Find the value of each unknown variable in the given figures ?
10) a. 130
Step-by-step explanation:
\(180 - 50 = 130\)
Two-fifths of the stage crew are girls. if there are 30 members of the stage crew, how many are girls?
Answer:
12 girls
Step-by-step explanation:
30*(2/5)=12
The lengths of two sides of a triangle are shown.
Side 1: 8x2 - 5x - 2
Side 2: 7x - x2 , 3
The perimeter of the triangle is 4xJ - 3x?
Part A: What is the total length of the two sides, 1 and 2, of the triangle? Show your work. (4 points)
Part B: What is the length of the third side of the triangle? Show your work. (4 points)
Part C: Do the answers for Part A and Part B show that the polynomials are closed under addition and subtraction? justify your answer. (2
points)
The Total length of two sides based on the information will be 7x²+2x+1
The Length of the third side will be 4 x³-10x²-7.
How to calculate the lengthTotal length of two sides= Side 1 + Side 2
= 8x² − 5x − 2+ 7x − x²+ 3
= 8x²-x²-5x+7x-2+3
= 7x²+2x+1
Length of the third side = Perimeter - Total length of two sides
Length of the third side=4x³ − 3x² + 2x − 6-(7x²+2x+1)
= 4x³ − 3x² + 2x − 6-7x²-2x-1
= 4 x³-10x²-7
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