Answer:
the number is 788......
If using the method of completing the square to solve the quadratic equation x 2 − 9 x − 8 = 0 x 2 −9x−8=0, which number would have to be added to "complete the square"?
Answer:
Add 81/4 to both sides.
Step-by-step explanation:
x^2 − 9x − 8 = 0
x^2 - 9x = 8
Take the coefficient of the x term: -9
Divide by 2: -9/2
Square it: 81/4
Add 81/4 to both sides.
HELP PLS ! ! !
What is |1 − 8i|?
A) √-65
B) 65
C) √65
D) √13
Answer:
C) SQRT(65)
Step-by-step explanation:
the magnitude of 1-8i is given by the following:
sqrt(a^2+b^2)
sqrt(1^2+8^2)
=sqrt(1+64)
=sqrt(65)
It is to be noted that the magnitude of |1 − 8i| is √(65) (Option C)
What is the computation of the above?To find the magnitude (or absolute value) of a complex number, we use the formula |a + bi| = √(a² + b²). In this case, the complex number is 1 - 8i.
Using the formula, we have -
|1 - 8i| = √(1² + (-8)²)
= √(1 + 64)
= √65
Hence, the magnitude of 1 - 8i is √65.
So the correct answer is C) √65.
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According to the American Academy of Cosmetic Dentistry, 75% of adults believe that an unattractive smile hurts career success. Suppose that 25 adults are randomly selected. What is the probability that 15 or more of them would agree with the claim?
Answer:
0.9703 = 97.03% probability that 15 or more of them would agree with the claim.
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they agree with the claim, or they do not. The probability of an adult agreeing with the claim is independent of any other adult, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
75% of adults believe that an unattractive smile hurts career success.
This means that [tex]p = 0.75[/tex]
Suppose that 25 adults are randomly selected.
This means that [tex]n = 25[/tex]
What is the probability that 15 or more of them would agree with the claim?
This is:
[tex]P(X \geq 15) = 1 - P(X < 15)[/tex]
In which:
[tex]P(X < 15) = P(X = 0) + P(X = 1) + P(X = 2) + ... + P(X = 13) + P(X = 14)[/tex]
14 is below the mean, so we start below and go until the probability is 0. Then
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 14) = C_{25,14}.(0.75)^{14}.(0.25)^{11} = 0.0189[/tex]
[tex]P(X = 13) = C_{25,13}.(0.75)^{13}.(0.25)^{12} = 0.0074[/tex]
[tex]P(X = 12) = C_{25,12}.(0.75)^{12}.(0.25)^{13} = 0.0025[/tex]
[tex]P(X = 11) = C_{25,11}.(0.75)^{11}.(0.25)^{14} = 0.0007[/tex]
[tex]P(X = 10) = C_{25,10}.(0.75)^{10}.(0.25)^{15} = 0.0002[/tex]
[tex]P(X = 9) = C_{25,9}.(0.75)^{9}.(0.25)^{16} \approx 0[/tex]
Then
[tex]P(X < 15) = P(X = 10) + P(X = 11) + P(X = 12) + P(X = 13) + P(X = 14) = 0.0002 + 0.0007 + 0.0025 + 0.0074 + 0.0189 = 0.0297[/tex]
And
[tex]P(X \geq 15) = 1 - P(X < 15) = 1 - 0.0297 = 0.9703[/tex]
0.9703 = 97.03% probability that 15 or more of them would agree with the claim.
what is the value of 3n +1 when n =4
Answer:
13
Step-by-step explanation:
since n is 4 substitute it where there's n in the equation
3(4)+1
12+1
13
I hope this helps
Answer:
13
Step-by-step explanation:
so you start with the equation 3n+1
since you know n=4 then u put it in place of n making the equation 3*4+1
then you multiply and it's 12+1 which equals 13
Stuck on this one!!
Shelly believes the honor roll students at her school have an unfair advantage in being assigned to the math class they request. She asked 500 students at her school the following questions: "Are you on the honor roll?" and "Did you get the math class you requested?" The results are shown in the table below:
Honor roll Not on honor roll Total
Received math class requested 125 215 340
Did not get math class requested 80 80 160
Total 205 295 500
Help Shelly determine if all students at her school have an equal opportunity to get into the math class they requested. Show your work, and explain your process for determining the fairness of the class assignment process.
Answer: No, there isn't equal opportunity
======================================================
Explanation:
Let's define the two events
A = person is on the honor rollB = person got the math class they requestedFrom the table, we see that
P(B) = 340/500 = 0.68
meaning that there's a 68% chance of picking someone who got the class they wanted (i.e. 68% of the people got the class they wanted)
------------
Now let's assume that the person is on the honor roll. This means we only focus on the "honor roll" column. There are 125 people here that got the class they wanted out of 205 honor roll students total.
So,
P(B given A) = 125/205 = 0.609756
which rounds to 0.61
This says that if a person is on the honor roll, then they have roughly a 61% chance of getting the class they want.
The chances have gone down from 68% to 61% roughly.
------------
It appears that being on the honor roll does affect your chances of getting into the class you want.
Therefore, all students do not have the same equal opportunity.
We would need to have P(B) and P(A given B) to be the same exact value for true equal opportunity to happen.
All students do not have equal opportunity.
From the table, we have the following parameters:
205 people are on honor roll call340 people got the math class requested500 people were surveyedThe above means that:
The probability that a person is on honor roll call is:
p1 = 205/500
p1 = 0.41
The probability that a person got the math class requested
p2 = 340/500
p2 = 0.68
Both probabilities are not equal.
Hence, it is true that all students do not have equal opportunity.
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Which line is parallel to y = -2x + 8
Answer:
y=-2x-7
Step-by-step explanation:
after putting the choices with the question in a graph I found that that ones stays in a line with the question
Brainliest please!!
Does the function ƒ(x) = (1∕2) + 25 represent exponential growth, decay, or neither?A) Exponential growth
B) Impossible to determine with the information given.
C) Neither
D) Exponential decay
Answer:
D) Exponential decay
Step-by-step explanation:
The correct function is:
[tex]f(x) = 25(1/2)^x[/tex]
Required
What type of rate is it
An exponential function is represented as:
[tex]f(x) = ab^x[/tex]
If
[tex]b > 0[/tex], then it represents growth
[tex]b < 0[/tex], then it represents decay
By comparison:
[tex]b = 1/2[/tex]
[tex]1/2 < 0[/tex]
Hence, the rate is exponential decay
Answer:
Step-by-step explanation:
. A ride at a county fair spins in a circle of radius (in meters). The centripetal force experienced by one of the passengers on the ride is modeled by the equation below, where is the number of seconds the ride takes to complete one revolution and is the mass (in kilograms) of the passenger. Tom, whose mass is kilograms is on a ride that is spinning in a circle at a rate of seconds per revolution. The radius of the circle is meters. Letting , how much centripetal force does Tom experience
Answer:
150 Newtons
Step-by-step explanation:
Given
[tex]t = \sqrt{\frac{4\pi^2mr}{F}}[/tex]
[tex]t = 12[/tex]
[tex]r =6.5[/tex]
[tex]\pi = 3.14[/tex]
[tex]m = 84.4[/tex]
See attachment
Required
Find F
We have:
[tex]t = \sqrt{\frac{4\pi^2mr}{F}}[/tex]
Square both sides
[tex]t^2 = \frac{4\pi^2mr}{F}[/tex]
Multiply both sides by F
[tex]Ft^2 = 4\pi^2mr[/tex]
Divide both sides by [tex]t^2[/tex]
[tex]F = \frac{4\pi^2mr}{t^2}[/tex]
Substitute known values
[tex]F = \frac{4*3.14^2*84.4*6.5}{12^2}[/tex]
[tex]F = \frac{21635.90624}{144}[/tex]
[tex]F = 150.249348889[/tex]
[tex]F = 150N[/tex]
A city has a population of 220,000 people suppose that each year the population grows by 8.75% what will the population be after 12 years
find the missing length indicated
explainion:
[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]
Use The (Pythagorean Theorem) to find the length of any side of a right triangle. Form it like its shown in picture above. Follow the instructions that also shown in the picture above.
I tried everything from adding to dividing, subtracting, multiplying but still no correct answer. Can someone help me out here please? Thank you for your time.
Answer:
68%
Step-by-step explanation:
6,753/100=67.53 which rounds up to 68%
6. If gallon A has 8L of water and gallon B has 800 ml of water, calculate the total volume of water in both the gallons.
Answer:
send me again I can't understand question
Solve the given differential equation by using an appropriate substitution. The DE is of the form dy/dx = f(Ax + By + C), which is given in (5) of Section 2.5. dy/dx = 4 + (y − 4x + 6)^1/2
dy/dx = 4 + √(y - 4x + 6)
Make a substitution of v(x) = y(x) - 4x + 6, so that dv/dx = dy/dx - 4. Then the DE becomes
dv/dx + 4 = 4 + √v
dv/dx = √v
which is separable as
dv/√v = dx
Integrating both sides gives
2√v = x + C
Get the solution back in terms of y :
2√(y - 4x + 6) = x + C
You can go on to solve for y explicitly if you want.
√(y - 4x + 6) = x/2 + C
y - 4x + 6 = (x/2 + C )²
y = 4x - 6 + (x/2 + C )²
substitute for A,P and T in the fomula A=P (1+r)^t,give that A=1 000 000,P=10 000 and T=2,and express as a quadratic equation
A = 10,00,000
P = 10,000
T = 2
1000000 = 10000(1+r/100)^2
1000000 = 10000((100 + r)/100)^2
1000000 = 10000× 100 + r/100 × 100 + r/100
1000000 = 10000 + r^2
1000000 - 10000 = r^2
990000 = r^2
√99000 = r
Quadratic Equation
10000(1+r/100)^2
Bill's father is three times Bill's age. Three years ago, Bill's father was four times Bill's age.
By forming two equations, find Bill's age now.
Answer:
12 and 36
Step-by-step explanation:
Call the age of both Bill and his father is a and b, respectively
we have:
b=3a
b-3=4(a-3) ->b=4a-12 -> 3a=4a-12 ->a =12 -> b=36
4 t-shirts and a hat costs £31.00
2 t-shirts and a hat costs £17.00.
How much does a t-shirt cost?
How much does a hat cost?
Answer:
t- shirt cost £7, hat cost £3
Step-by-step explanation:
let t represent cost of t- shirt and h represent cost of hat , then
4t + h = 31 → (1)
2t + h = 17 → (2)
Subtract (2) from (1) term by term to eliminate h
(4t - 2t) + (h - h) = 31 - 17 , that is
2t = 14 ( divide both sides by 2 )
t = 7
Substitute t = 7 into either of the 2 equations and solve for h
Substituting into (1)
4(7) + h = 31
28 + h = 31 ( subtract 28 from both sides )
h = 3
t- shirt cost £7 and hat cost £3
HEYYYYYYYYYYYYYYY
PLEASE HELP AND BE CORRECT ANSWER AT THE BOTTOM
TELL ME WHERE TO PUT THE POINTS
Answer:
y = -3 (you have to draw an horizontal line that passes for the point (0,-3)
Step-by-step explanation:
We have to find the middle points of the segments that unite the corrispettive points.
We are lucky because the images of the points have the same x coordinate of the original ones, so we have just to find the y coordinates.
Segment CC‘
(y1 + y2)/2 = (-1-5)/2 = -3
Segment AA’
(0-6)/2 = -3
Segmet BB’
(1-7)/2 = -3
Segment DD’
(1-7)/2 = -3
In conclusion we can say that the points of the reflection have all the y coordinate equal to -3.
the line is horizontal and its equation is : y = -3
3x+2y <
11 2x-y<9
Does this graph match this equation?
Answer:
No.
Step-by-step explanation:
3x+2y<11 doesn't have a y-intercept of 6 and doesn't have a x-intercept of 4.
2x-y<9 is not the same direction as 3x+2y<11.
A newsstand spends $600 a month on rent and electricity, and it spends $2
for each magazine that it sells. The newsstand charges $5 for each
magazine. If n is the number of magazines, which equation represents the
profit function of the newsstand?
O A. p = 2n + 600
B. p = 3n-600
O c. p = 600n + 3
O D. p = 5n-600
Answer: B. p = 3n-600
Step-by-step explanation:
Cost = 2n + 600Earned = 5nProfit(p) = Earned - Cost
p = 5n - (2n + 600) = 5n - 2n - 600 = 3n - 600
The equation representing the profit function of the newsstand is
p = 3n - 600
Option B is the correct answer.
What is a function?A function has an input and an output.
A function can be one-to-one or onto one.
It simply indicated the relationships between the input and the output.
Example:
f(x) = 2x + 1
f(1) = 2 + 1 = 3
f(2) = 2 x 2 + 1 = 4 + 1 = 5
The outputs of the functions are 3 and 5
The inputs of the function are 1 and 2.
We have,
The revenue generated by selling n magazines is 5n dollars.
The cost of selling n magazines is the sum of the cost of purchasing n magazines and the fixed cost of rent and electricity, which is $2n + $600.
Now,
The profit function can be represented by:
p = revenue - cost
= 5n - (2n + 600)
= 3n - 600
Thus,
The equation representing the profit function of the newsstand is
p = 3n - 600
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There are 45 applicants for two Software
Maker positions.
I
enter the number that belongs in the green box
5x - 2 = 4 + 2x
3x - 2 = 4
3x = 6
x = 2
Hope this helps!
what is sqrt 2x-3 = sqrt 3x-9
Answer:
x=6
Step-by-step explanation:
sqrt (2x-3) = sqrt (3x-9)
Square each side
(sqrt (2x-3))^2 = (sqrt (3x-9))^2
2x-3 = 3x-9
Subtract 2x from each side
2x-3-2x = 3x-2x-9
-3 = x-9
Add 9 to each side
-3+9 = x-9+9
6 =x
Check solution
sqrt (2*6-3) = sqrt (3*6-9)
sqrt (9) = sqrt (9)
3=3
Solution is valid
sqrt (2x-3) = sqrt (3x-9)
Square each side
(sqrt (2x-3))^2 = (sqrt (3x-9))^2
2x-3 = 3x-9
Subtract 2x from each side
2x-3-2x = 3x-2x-9
-3 = x-9
Add 9 to each side
-3+9 = x-9+9
6 =x
sqrt (2*6-3) = sqrt (3*6-9)
sqrt (9) = sqrt (9)
3=3
Therefore ans x = 6
Answered by Gauthmath must click thanks and mark brainliest
Study the scatterplot and trend line. Which two points can be used to find the equation of the trend line?
Which points are on the trend line?
(1, 30) and (9, 95)
(2, 30) and (6, 70)
(2, 45) and (8, 90)
(3, 50) and (7, 65)
Answer:
C
Step-by-step explanation:
Just trust
Answer:
C
Step-by-step explanation:
I did the assignment in edge and got it right.
Proof:
Suppose you choose a marble from a bag containing 4 red marbles, 2 white marbles, and 3 blue marbles. You return the first marble to the bag and then choose again. Find P(red then blue).
Answer:
4/27
Step-by-step explanation:
total number of marbles=9
probability of red=4/9
since you returned the first marble, the total number of marbles remains the same
prob(Blue)=(3/9)=1/3
P(red then blue)=(4/9)*(1/3)
=4/27
The purchase price of a new machine is 3500 000 dinars. its value will decrease by
300 000 dinars each year.write a linear model that expresses the value of the
machine (t) years after its purchased :
A) p = 300 000 -3500000t
B) p = 3500 000 +300000t
C) p = 3500 000-300000t
D) p = 300 000+3500000t
I need help guys thanks so much
Answer: A & C
Step-by-step explanation:
[tex]i=\sqrt{-1}[/tex]
[tex]\sqrt{-1} *\sqrt{4} =\sqrt{-4}[/tex]
You can also simplify the above by taking the -4 out of the radical
It becomes 2 x [tex]\sqrt{-1}[/tex], which can be simplifed to C
In this problem, assume that the probability that a person is born on a given day is 1/365. (For simplicity, ignore Feb 29.) In a group of 100, what is the expected number of pairs of people who have the same birthday
Answer:
the expected number of pairs of people who have the same birthday is 14
Step-by-step explanation:
The computation of the expected number of pairs of people who have the same birthday is as follows:
= 100 (100 - 1) ÷ 2 × 365
= 100 × 99 ÷ 730
= 9900 ÷ 730
= 13.5616
= 14
Therefore, the expected number of pairs of people who have the same birthday is 14
i need some help with this question. it says find x
Answer:
x = 9.8
Step-by-step explanation:
Please see attached photo for diagram.
We'll begin by calculating the value of y. This can be obtained as follow:
Angle θ = 45
Opposite = 6
Hypothenus = y
Sine θ = Opposite /Hypothenus
Sine 45 = 6/y
0.7071 = 6/y
Cross multiply
y × 0.7071 = 6
Divide both side by 0.7071
y = 6 / 0.7071
y = 8.5
Finally, we shall determine the value of x. This can be obtained as follow:
Angle θ = 60
Opposite = 8.5
Hypothenus = x
Sine θ = Opposite /Hypothenus
Sine 60 = 8.5 / x
Cross multiply
x Sine 60 = 8.5
Divide both side by sine 60
x = 8.5 / sine 60
x = 8.5 / 0.8660
x = 9.8
An unknown number becomes 30 when rounded to the nearest ten. Which could NOT be the unknown number?
A. 24
B. 25
C. 28
D. 31
Answer:
A. 24
Step-by-step explanation:
Five and above rounds up
so 25,26,27,28,29 rounds up to 30
We leave it alone when 4 or less
34,33,32,31,30 remains at 30
24 would not round to 30
A line passes through the point (-3, -3) and has a slope of 1/2 What is the equation of the line?
Answer:
y= 1/2x-3/2
Step-by-step explanation:
The slope intercept form of a line is
y = mx+b where m is the slope and b is the y intercept
y = 1/2x+b
Using the point for x and y we can find b
-3 = 1/2(-3)+b
-3 = -3/2 +b
-6/2 = -3/2+b
Add 3/2 to each side
-6/2 +3/2 = b
-3/2 = b
y= 1/2x-3/2
Answer:
Step-by-step explanation:
y + 3 = 1/2(x + 3)
y + 3 = 1/2x + 3/2
y + 6/2 = 1/2x + 3/2
y = 1/2x - 3/2
