Answer:
1: A=1
2: -3
3: C
Step-by-step explanation:
1: If 3x+4 is a factor, then -4/3 is equal to x. Substitute it in for x and solve for a. This gives us A=1.
For the commenter not understanding how I got -4/3: 3x+4 being a factor means that it equals 0. It might help you understand this if you remember that after factoring, like I did for 38 in my photo, we take expressions like x-4 and set them equal to 0 to get x=4, a solution. So, subtract 4 from both sides to get 3x=-4, then divide both sides by 3 to get x alone. Thus, x=-4/3.
2: To find the sum, we first need to find the two solutions. We can factor to get (x+7)(x-4). This gives us x=-7 and x=+4. The solution of these two would be (-7)+4 is -3.
3: B is a close answer, but the signs are wrong on the bottom. Factoring the question would give us 2(x-2) / 2(x^2-x-2). Factoring that equation is 2(x-2) / 2(x+1)(x-2). Simplifying this gives us 1 / x+1.
Sorry for the bad penmanship, I wanted to make it a little clearer for you! I really hope I helped! :)
An economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in Texas. He believes that the mean income is $30.8, and the standard deviation is known to be $8.2. How large of a sample would be required in order to estimate the mean per capita income at the 95% level of confidence with an error of at most $0.39
Answer:
A sample of 1699 would be required.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Standard deviation is known to be $8.2.
This means that [tex]\sigma = 8.2[/tex]
How large of a sample would be required in order to estimate the mean per capita income at the 95% level of confidence with an error of at most $0.39?
This is n for which M = 0.39. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.39 = 1.96\frac{8.2}{\sqrt{n}}[/tex]
[tex]0.39\sqrt{n} = 1.96*8.2[/tex]
[tex]\sqrt{n} = \frac{1.96*8.2}{0.39}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*8.2}{0.39})^2[/tex]
[tex]n = 1698.3[/tex]
Rounding up:
A sample of 1699 would be required.
what is the value of k
Answer:
(A)
Step-by-step explanation:
M=-2
therefore
x¹=3, y¹=-12, x²=6 y²=k
M=(y²-y¹)/(x²-x¹)
-2=(k+12)/(6-3)
-2×3=k+12
-6=k+12
k=-18
Differentiate the following Functions
5x^2-2xy + 4y^3= 5
Answer:
[tex]\displaystyle y' = \frac{y - 5x}{x + 6y^2}[/tex]
General Formulas and Concepts:
Algebra I
Terms/CoefficientsFactoringCalculus
Differentiation
DerivativesDerivative NotationImplicit DifferentiationDerivative Property [Multiplied Constant]: [tex]\displaystyle \frac{d}{dx} [cf(x)] = c \cdot f'(x)[/tex]
Derivative Property [Addition/Subtraction]: [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]
Basic Power Rule:
f(x) = cxⁿf’(x) = c·nxⁿ⁻¹Derivative Rule [Product Rule]: [tex]\displaystyle \frac{d}{dx} [f(x)g(x)]=f'(x)g(x) + g'(x)f(x)[/tex]
Derivative Rule [Chain Rule]: [tex]\displaystyle \frac{d}{dx}[f(g(x))] =f'(g(x)) \cdot g'(x)[/tex]
Step-by-step explanation:
Step 1: Define
Identify
[tex]\displaystyle 5x^2 - 2xy + 4y^3 = 5[/tex]
Step 2: Differentiate
Implicit Differentiation: [tex]\displaystyle \frac{dy}{dx}[5x^2 - 2xy + 4y^3] = \frac{dy}{dx}[5][/tex]Rewrite [Derivative Property - Addition/Subtraction]: [tex]\displaystyle \frac{dy}{dx}[5x^2] - \frac{dy}{dx}[2xy] + \frac{dy}{dx}[4y^3] = \frac{dy}{dx}[5][/tex]Rewrite [Derivative Property - Multiplied Constant]: [tex]\displaystyle 5\frac{dy}{dx}[x^2] - 2\frac{dy}{dx}[xy] + 4\frac{dy}{dx}[y^3] = \frac{dy}{dx}[5][/tex]Basic Power Rule [Chain Rule]: [tex]\displaystyle 10x - 2\frac{dy}{dx}[xy] + 12y^2y' = 0[/tex]Product Rule: [tex]\displaystyle 10x - 2\bigg[ \frac{dy}{dx}[x]y + x\frac{dy}{dx}[y] \bigg] + 12y^2y' = 0[/tex]Basic Power Rule [Chain Rule]: [tex]\displaystyle 10x - 2\bigg[ y + xy' \bigg] + 12y^2y' = 0[/tex]Simplify: [tex]\displaystyle 10x - 2y + 2xy' + 12y^2y' = 0[/tex]Isolate y' terms: [tex]\displaystyle 2xy' + 12y^2y' = 2y - 10x[/tex]Factor: [tex]\displaystyle y'(2x + 12y^2) = 2y - 10x[/tex]Isolate y': [tex]\displaystyle y' = \frac{2y - 10x}{2x + 12y^2}[/tex]Factor: [tex]\displaystyle y' = \frac{2(y - 5x)}{2(x + 6y^2)}[/tex]Simplify: [tex]\displaystyle y' = \frac{y - 5x}{x + 6y^2}[/tex]Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Differentiation
Book: College Calculus 10e
(-4/9)*3×(-27/20)*4=
(-4/9)*3×(-27/20)*4= 7.2
Step-by-step explanation:
here's the answer to your question
A tourist from Britain wants to exchange her British pounds for US dollar. She has 25 British pounds. How many US dollars would she get in exchange for her British pound if 1 British pound can be exchanged for 1.53 US dollars?
Answer:
$38.25 US dollars.
Step-by-step explanation:
25 / 1 = 25
To find the number of US dollars that can be exchanged for 25 British pounds, multiply 1.53 by 25 to get $38.25 US dollars.
Hope this helps!
if there is something wrong, just let me know.
Help please anyone???
9514 1404 393
Answer:
x^2/1 +y^2/81 = 1
Step-by-step explanation:
We know that the equation of a unit circle is ...
x^2 +y^2 = 1 . . . . . equation of a unit circle
We also know that replacing x with x/a in a function will expand the graph by a factor of 'a'. Similarly, replacing y with y/b will do the same in the vertical direction.
An ellipse is a circle that has had different expansion factors applied along its different axes. Here, the given points tell us the center of the ellipse is (0, 0), and that it has been expanded by a factor of 9 in the y-direction and a factor of 1 in the x-direction This means the equation for it would be ...
(x/1)^2 +(y/9)^2 = 1 . . . . . equation for desired ellipse
In the required form, this is ...
[tex]\dfrac{x^2}{1}+\dfrac{y^2}{81}=1[/tex]
The area of the rectangle and square are equal find x.
Answer:
10 =x
Step-by-step explanation:
The area of the square is
A = s^2 where s is the side length
A = 6^2 = 36
The area of the rectangle is
A = l*w
A = 3(x+2) = 3x+6
We know the areas are equal
36 = 3x+6
Subtract 6 from each side
36-6 = 3x+6-6
30 = 3x
Divide by 3
30/3 = 3x/3
10 =x
Answer:
10
Step-by-step explanation:
Square area = b × h
SA = 6 × 6 = 36
The square's area equals 36.
Rectangle area = b × h
RA = 3 × (x + 2)
36 = 3(x + 2)
36 = 3x + 6
-6 -6
----------------
30 = 3x
---- ----
3 3
10 = x
The answer is 10.
Hope this helped.
I NEED HELP PLEASE!!
Answer:
70
Step-by-step explanation:
70 because as the number of trials increase, the actual ratio of outcomes will converge on the expected ratio.
Of the people surveyed, 1/4 watch Channel NineNews. What is this as a percentage?
A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, test the claim that at least half of all voters prefer the Democrat.
a. Identify the null and alternative hypotheses.
b. Find the test statistic and P-value.
c. State the conclusion about the null hypothesis.
d. State the final conclusion that addresses the original claim.
Answer:
Step-by-step explanation:
H0 = .5 prefer Democratic candidate
Ha > .5 prefer Democratic candidate
p = .48
z = -1.285179129
0.9006 >= .05 thus we "FAIL TO REJECT THE NULL HYPOTHESES"
Laura makes a sound that 80.9 dB loud. Sarah makes a sound that is 3 time as intense. What is the loudness of Sarah's sound (in dB)
Answer:
242.7 dB
Step-by-step explanation:
If the mean of a given dataset is
42 and the standard deviation is
4, where will a majority of the
data lie?
Answer:
A majority of the data will lie between 38 and 46.
Step-by-step explanation:
It can be said that a majority of the data of a distribution lies within 1 standard deviation of the mean.
In this question:
Mean of 42, standard deviation of 4.
42 - 4 = 38
42 + 4 = 46
A majority of the data will lie between 38 and 46.
I don't know how to do this. Please help
Answer:
63m³
Step-by-step explanation:
volume of a cylinder = πr²h
r = 2m, h = 5m
= 22/7 × 2² × 5
= 62.86m³
approx 63m³
Drag the tiles to the boxes to form correct pairs. Not all tiles will be used.
Match the binomial quadratic expressions with their factored form.
Answer:
x²-36 and (x-6)(x+6)
9x-1 and(3x-1)(3x+1)
4x² -16 and 4(x-2)(x+2)
Step-by-step explanation:
when you multiply(x+6)(x-6)
you get x²-36,this is known as difference of two squares ie (a+b)(a-b)=(a²-b²)=0
x(x-6)+6(x-6)
x²-6x+6x-36
x² -36
the second the same explanation as the first
for the third, multiply (x+2)(x-2) it will give x²-4
then multiply this by 4 which is = 4x² - 16
Please help with this qns
9514 1404 393
Answer:
$70
Step-by-step explanation:
Four relationships are given among four unknowns. Define the following variables: p, c -- the cost of a pie and a cake, respectively. q, d -- the number of pies and cakes, respectively.
q/d = 5/2 . . . . . the ratio of pies to cakes sold
pq +cd = 3780 . . . . revenue from the sales
p = c -35 . . . . . a pie is $35 less than a cake
cd = pq -420 . . . . revenue from cakes is $420 less than for pies
__
The equations are non-linear, so we're making up this process as we go along. We observe that 'pq' and 'cd' are involved in relations that give us their sum and difference, so these products are easily found. Their ratio can let us take advantage of our knowledge of q/d.
Substituting for cd in the second equation, we get ...
pq +(pq -420) = 3780
2pq = 4200
pq = 2100
cd = 2100 -420 = 1680
Now, we can write ...
pq/cd = 2100/1680 = 5/4
(p/c)(q/d) = 5/4 = (p/c)(5/2) . . . . substitute for q/d
p/c = 1/2 = (c -35)/c . . . . . . . . . . substitute for p
c = 2(c -35) . . . . multiply by 2c
c = 70 . . . . . . . . add 70-c
The cost of a cake is $70.
_____
Additional comment
24 cakes were sold at $70 each. 60 pies were sold at $35 each.
the incenter of a triangle is formed by the intersection of the of a triangle
Answer:
angle bisectors
Step-by-step explanation:
The incentre is where a triangle's three angle bisectors intersect ( an angle bisector is a ray that cuts an angle in half ). The incentre is the centre of a triangle drawn inside the triangle.
Find the standard deviation for the following group of data items.
9, 11, 11, 16
The standard deviation for the given data items is 2.6
The standard deviation of the given data items can be calculated by taking the square root of the variance.
Variance is a measure of variability and it is calculated by taking the average of squared deviations from the mean.
Hence, we will first determine the mean of the given data items.
Mean is simply the average of the numbers.
Therefore mean of the given data items is
[tex]Mean = \frac{9+11+11+16}{4}[/tex]
[tex]Mean = \frac{47}{4}[/tex]
Mean = 11.75
Now, for the variance of the data
[tex]Variance = \frac{(9-11.75)^{2}+(11-11.75)^{2}+(11-11.75)^{2}+(16-11.75)^{2} }{4}[/tex]
[tex]Variance = \frac{(-2.75)^{2}+(-0.75)^{2}+(-0.75)^{2}+(4.25)^{2} }{4}[/tex]
[tex]Variance = \frac{7.5625+0.5625+0.5625+18.0625}{4}[/tex]
[tex]Variance = \frac{26.75}{4}\\[/tex]
∴ Variance = 6.6875
But,
Standard deviation [tex]= \sqrt{Varinace}[/tex]
∴Standard deviation [tex]=\sqrt{6.6875}[/tex]
Standard deviation = 2.586
Standard deviation ≅ 2.6
Hence, the standard deviation for the given data items is 2.6
Learn more on standard deviation here: https://brainly.com/question/18562832
Urgent need the answers plz help.
Answer:
(a) [tex]P" = (-4,-3)[/tex]
(b) [tex](x,y) \to (4,-8)[/tex]
Step-by-step explanation:
Given
[tex]P = (4,3)[/tex]
Solving (a): Reflect across x and y-axis.
Reflection across x-axis has the following rules
[tex](x,y) \to (x,-y)[/tex]
So, we have:
[tex]P' = (4,-3)[/tex]
Reflection across y-axis has the following rules
[tex](x,y) \to (-x,y)[/tex]
So, we have:
[tex]P" = (-4,-3)[/tex]
Hence, the new point is: (-4,-3)
Solving (b): Rx . Do,2 (2,4)
[tex]R_x \to[/tex] reflect across the x-axis
Reflection across x-axis has the following rules
[tex](x,y) \to (x,-y)[/tex]
So, we have:
[tex](2,4) = (2,-4)[/tex] ---- when P is reflected across the x-axis
[tex]D_{o,2} \to[/tex] dilate by a scale factor of 2
The rule is:
[tex](x,y) \to 2 * (x,y)[/tex]
So, we have
[tex](x,y) \to 2 * (2,-4)[/tex]
Open bracket
[tex](x,y) \to (4,-8)[/tex]
a company has decreased the weight of its boxes of macaroni by 8 %. if the new weight of the box is 13.1ounces, what was the original weight of the box?
Answer:
실례합니다 ?
Step-by-step explanation:
이것이 무엇을 의미하는 질문입니까?
회사는 마카로니 상자의 무게를 8% 줄였습니다. 상자의 새 무게가 13.1온스인 경우 상자의 원래 무게는 얼마였습니까? 오른쪽 ?
Answer:
x*0.92 = 13.1
x = 14.24
Step-by-step explanation:
(x+7)(x-6) Find the product.ddddddddddddd
Answer:
x^2 + x - 42
Step-by-step explanation:
use the distributive property:
(x+7)(x-6) = x^2 + x - 42
Answer: x^2 + x - 42
Step-by-step explanation:
prove:
sin²A-cos²B=sin²B-cos²A
Step-by-step explanation:
thwashm m GB DC GM 3hka it g feeds ygzdkzyzuzjz indin, mi, hn zbe
Answer:
Solution given:
L.H.S
sin²A-cos²B
we havesin²A=1-cos²A and Cos²B=1-sin²B
nowreplacing value
1-cos²A-(1-sin²B)
open bracket1-cos²A-1+sin²B
keep together like terms1-1+sin²B-Cos²A
=sin²B-Cos²A
R.H.S
proved.Help me please and thank you
Step-by-step explanation:
jlejej
are u using chrome os
Which fraction is greater than the fraction represented by the model?
HURRY PLS IM BEING TIMED!!!!
Answer:
7/16
Step-by-step explanation:
7/16>3/8
It would be 7/16 because 3/8 is what is being shown. If you make them both have a common denominator then it would be 6/16.
PLEAZE HELPPPPPPPSPPSPAP
Answer:
Step-by-step explanation:
345ftyfthftyft.plk,k,
Answer:
Hello,
Anwser is C
Step-by-step explanation:
[tex]y=log_9(12x)\\\\9^y=12x\\\\9^x=12y\ inverting \ x \ and \ y \\\\y=\dfrac{9^x}{12} \\[/tex]
Using the order of operations, what is the last calculation that should be done to evaluate 4(8 - 6952 - 6+(-3)
4(8 - 6352 – 6 + (-3)
4(2)52 - 6+(-3)
4(2)(25) - 6+(-3)
200 - 6+(-3)
200 - (-2)
Answer:
200 + 2
Step-by-step explanation:
you know that two (2) negatives multiplying each other is = +
=200 +2
=202
A study is conducted to compare the lengths of time required by men and women to assemble a certain product. Past experience indicates that the distribution of times for both men and women is approximately normal but the variance of the times for women is less than that for men. A random sample of times for 11 men and 14 women produced the following data:
Men:
n1= 11
s1= 6.1
Women:
n2= 14
s2= 5.3
Test the hypothesis that the variance for men is greater than for women. Use both p-value method and critical value approach.
Answer:
1.33 < 2.67 ; Fail to reject H0 at 0.05
Step-by-step explanation:
Given the data :
Men:
n1= 11
s1= 6.1
Women:
n2= 14
s2= 5.3
The hypothesis :
H0 : σ1² = σ2²
H1 : σ1² > σ2²
To calculate the test statistic ; we use th Ftest statistics ;
F statistic = Larger sample variance / Smaller sample variance
Fstatistic = s1² / s2² = 6.1² / 5.3² = 37.21/28.09 = 1.325
The F critical value at :
df numerator = n - 1 = 11 - 1 = 10
df denominator = n - 1 = 14 - 1 = 13
Using the F distribution table :
F critical = 2.671
Since
F statistic < F critical ; Fail to reject H0 at 0.05
We fail to reject the null hypothesis at significance level of H0 : s1² = s2²
For the men, we have:
n1= 11 s1= 6.1
For the women, we have:
n2= 14 s2= 5.3The null and the alternate hypotheses are:
Null hypothesis H0 : s1² = s2²Alternate hypothesis H1 : s1² > s2²
The numerator and the denominator degrees of freedom are calculated as:
[tex]\mathbf{df = n -1}[/tex]
So, we have:
[tex]\mathbf{df_1 = 11 -1}[/tex]
[tex]\mathbf{df_1 = 10}[/tex] ----- numerator
[tex]\mathbf{df_2 = 14 -1}[/tex]
[tex]\mathbf{df_2 = 13}[/tex] ----- denominator
The test statistic of the f test is:
[tex]\mathbf{t = \frac{s_1^2}{s_2^2}}[/tex]
So, we have:
[tex]\mathbf{t = \frac{6.1^2}{5.3^2}}[/tex]
[tex]\mathbf{t = \frac{37.21}{28.09}}[/tex]
[tex]\mathbf{t = 1.325}[/tex]
The critical values at [tex]\mathbf{t = 1.325}[/tex] and the degrees of freedom is:
[tex]\mathbf{F= 2.671}[/tex]
By comparison, 1.325 is less than 2.671.
Hence, we fail to reject the null hypothesis at H0 : s1² = s2²
Read more about hypothesis at:
https://brainly.com/question/23639322
solve for x
8x2-5=11
Answer:
1
Explainion show in picture above
Answer:
x=6
Step-by-step explanation:
It should be 8+x+2-5=11
Find the face value of the 20-year zero-coupon bond at 4.4%, compounded semiannually, with a price of $8,375.
$45.000
$53.000
The correct face value will be Option C ($20,000). A further solution id provided below.
Given:
Time,
t = 20 years
Rate,
r = 4.4%
Price
= $8,375
Now,
The yield will be:
= [tex]\frac{4.4}{2}[/tex]
= [tex]1.1[/tex] (%)
Time will be:
= [tex]20\times 2[/tex]
= [tex]40 \ periods[/tex]
As we know the formula,
⇒ [tex]Price \ of \ bond = \frac{Face \ value}{(1+\frac{r}{2} )^{n\times 2}}[/tex]
By substituting the values, we get
[tex]8375=\frac{Face \ value}{(1+\frac{0.044}{2} )^{20\times 2}}[/tex]
[tex]8375=\frac{Face \ value}{(1.022)^{40}}[/tex]
[tex]8375=\frac{Face \ value}{2.3880083}[/tex]
The face value will be:
[tex]Face \ value = 2.3880083\times 8375[/tex]
[tex]=20,000[/tex] ($)
Learn more about face value here:
https://brainly.com/question/14862802
Cars arrive at a toll booth according to a Poisson process with mean 90 cars per hour. Suppose the attendant makes a phone call. How long, in seconds, can the attendant's phone call last if the probability is at least 0.1 that no cars arrive during the call
Answer:
92.12 seconds
Step-by-step explanation:
According to the poisson probability relation :
P(X =x) = (e^-λ * λ^x) / x!
For no calls to be reveived during the period, x = 0
P(X = 0) = (e^-λ * λ^0) / 0!
P(X = 0) = 0.1
0.1 = (e^-λ * λ^0) / 0!
0.1 = e^-λ
Take the In of both sides
In(0.1) = - λ
-2.303 = - λ
λ = 2.303
The length of call in second, l
l = λ / r ; r = arrival rate
r = 90 per hour ; this means ;
90 / 3600 = 0.025
l = 2.303 / 0.025
l = 92.12 seconds
Y<3/2•x-4
Match the equation to a graph.
Answer:
Last option
Step-by-step explanation:
The slope 3/2 determines the line (although you can plot points to find (0,-4) and (4,2), connecting them, you'll get the equation of the line, and the area it covers will be to the right side, putting x = 0, y<-4, which is below the line, that's how you determine it.
Answered by GAUTHMATH