Answer:
Substitute into the quadratic formula
-6 ± √32 / 2
= -3 ± √16
= 1 and -1 are the answer
Answer:
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Given
x² + 6x + 1 = 0 ( subtract 1 from both sides )
x² + 6x = - 1
Using the method of completing the square
add/ subtract ( half the coefficient of the x- term)² to both sides
x² + 2(3)x + 9 = - 1 + 9
(x + 3)² = 8 ( take the square root of both sides )
x + 3 = ± [tex]\sqrt{8}[/tex] = ± 2[tex]\sqrt{2}[/tex] ( subtract 3 from both sides )
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Then
x = - 3 - 2[tex]\sqrt{2}[/tex] , x = - 3 + 2[tex]\sqrt{2}[/tex]
A carpet expert believes that 9% of Persian carpets are counterfeits. If the expert is right, what is the probability that the proportion of counterfeits in a sample of 686 Persian carpets would differ from the population proportion by greater than 3%
Answer:
0.0060 = 0.6% probability that the proportion of counterfeits in a sample of 686 Persian carpets would differ from the population proportion by greater than 3%
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
A carpet expert believes that 9% of Persian carpets are counterfeits.
This means that [tex]p = 0.09[/tex]
Sample of 686:
This means that [tex]n = 686[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.09[/tex]
[tex]s = \sqrt{\frac{0.09*0.91}{686}} = 0.0109[/tex]
What is the probability that the proportion of counterfeits in a sample of 686 Persian carpets would differ from the population proportion by greater than 3%?
Proportion lower than 9% - 3% = 6% or higher than 9% + 3% = 12%. The normal distribution is symmetric, thus these probabilities are equal, so we can find one of them and multiply by 2.
Probability it is lower than 6%
p-value of Z when X = 0.06. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.06 - 0.09}{0.0109}[/tex]
[tex]Z = -2.75[/tex]
[tex]Z = -2.75[/tex] has a p-value of 0.0030
2*0.0030 = 0.0060
0.0060 = 0.6% probability that the proportion of counterfeits in a sample of 686 Persian carpets would differ from the population proportion by greater than 3%
Which rations are equivalent to 30:20? check all that apply
Answer:
3:2, 6;4 hope this helps
Answer:
C, D
Step-by-step explanation:
If you multiply both numbers of a ratio by the same number, you get an equivalent ratio.
A. Divide both numbers by 10
40:30 = 4:3 No
B. 10:0 No
C. Multiply both numbers by 10
3:2 = 30:20 Yes
D. Multiply both numbers by 5
6:4 = 30:20 Yes
Marina spent $13.50 at the grocery store. She bought pears, kiwis, and pineapples. Pears cost $0.50 each, pineapples cost $1.50 each, and kiwis are $0.30 each.How many of each kind did she buy if she bought 9 more pears than pineapples and 2 fewer kiwis than pears? Branliest if correct.
Answer:
Number of pineapples = 10
Number of pears = 10 + 9 = 19
Number of kiwis = 10 - 2 = 8
Step-by-step explanation:
Money = $ 13.5
Cost of a pear = $ 0.5
Cost of a pineapple = $ 1.5
Cost of a kiwi = $ 0.3
let the number of pineapple = p
Number of pears = p + 9
Number of kiwis = p - 2
Cost is
0.5 (p + 9) + 0.15 p + 0.3 (p - 2) = 13.5
0.5 p + 4.5 + 0.15 p + 0.3 p - 0.6 = 13.5
0.95 p = 9.6
p = 10
So, number of pineapples = 10
Number of pears = 10 + 9 = 19
Number of kiwis = 10 - 2 = 8
Answer:
3 pineapples 12 pears 10 kiwis
What is the true solution to the equation below?
l n e Superscript l n x Baseline + l n e Superscript l n x squared Baseline = 2 l n 8
x = 2
Given:
The equation is:
[tex]\ln e^{\ln x}+\ln e^{\ln x^2}=2\ln 8[/tex]
To find:
The solution for the given equation.
Solution:
We have,
[tex]\ln e^{\ln x}+\ln e^{\ln x^2}=2\ln 8[/tex]
It can be written as:
[tex]\ln x+\ln x^2=2\ln 8[/tex] [tex][\because \ln e^x=x][/tex]
[tex]\ln (x\cdot x^2)=2\ln 8[/tex] [tex][\because \ln a+\ln b=\ln (ab)][/tex]
[tex]\ln (x^3)=\ln 8^2[/tex] [tex][\because \ln x^n=n\ln x ][/tex]
On comparing both sides, we get
[tex]x^3=8^2[/tex]
[tex]x^3=64[/tex]
Taking cube root, we get
[tex]x=\sqrt[3]{64}[/tex]
[tex]x=4[/tex]
Therefore, the required solution is [tex]x=4[/tex].
Answer:
x=4
Step-by-step explanation:
What is the true solution to the equation below?
ln e Superscript ln x Baseline + ln e Superscript ln x squared Baseline = 2 ln 8
x = 2
x = 4
x = 8
F(x) = x/2*8 what is f(x), when x=10
Answer
13
Step-by-step explanation:
We are essentially being asked to find f(10), so let's evaluate this function at 10 by plugging this in for x.
f(10)=10/2+8=5+8=13
Answer:
f(x) = 40
Step-by-step explanation:
f(x) = x / 2 * 8
x = 10
f(x) = (10 / 2) * 8
= 5 * 8
= 40
what are the missing numbers ?
Kim ran 9/10 of a mile. Adrian ran 3/5 of a mile Adrian claims that Kim ran 1 3/10 times farther than him Kim says that she actually ran 1/2 times farther than Adrian who is correct
9514 1404 393
Answer:
Kim
Step-by-step explanation:
The ratio of Kim's distance to Adrian's distance is ...
(9/10)/(3/5) = (9/10)/(6/10) = 9/6 = 3/2 = 1.5
__
You need to be very careful with the wording here. Kim ran 1 1/2 times as far as Adrian. That is, she ran Adrian's distance plus 1/2 Adrian's distance.
If we take the wording "1/2 times farther" to mean that 1/2 of Adrian's distance is added to Adrian's distance, then Kim is correct.
_____
In many Algebra problems, you will see the wording "k times farther" to mean the distance is multiplied by k. If that interpretation is used here, neither claim is correct, as Kim's distance is 1 1/2 times farther than Adrian's.
On the other hand, if the value of "k" is expressed as a percentage, the interpretation usually intended is that that percentage of the original distance is added to the original distance. Using this interpretation, Kim's distance is 50% farther than Adrian's. (Note the word "times" is missing here.)
__
Since Adrian ran 1 5/10 the distance Kim ran, Adrian's claim is incorrect regardless of the interpretation. If you require one of the two to be correct, then Kim is.
Exercise
a. I choose the correct option from Contain Questions
i Which of the following is a group set ?
(b) A happy person in the Village
(c) Simple Ex in the book (d) school age student
(Weekly
Answer:
happy person in the village
Can you answer this an help me with this question an others ??
Answer:
D. The y-intercept of the new graph would shift down 2 units.
Step-by-step explanation:
y = -9x + 3 has a y-intercept of 3 (0, 3).
y = -9x + 1 has a y-intercept of 1 (0, 1).
3 - 1 = 2
So, down two units.
Joanne's monthly salary is $2400.she spend's ⅒ of it on food and ⅜ of it on leisure activities.How much does she have left?
Answer:
1200$
please mark me as brain liest
Gemma recently rode her bicycle to visit her friend who lives 6 miles away. On her way there, her average speed was 16 miles per hour faster than on her way home. If Gemma spent a total of 1 hour bicycle, find the two rates.
first speed --- x mph
return speed -- x+16 mph
6/x + 6/(x+16) = 1
times each term by x(x+16)
6(x+16) + 6x = x(x+16)
x^2 + 4x - 96 = 0
(x-8)(x+12) = 0
x = 8 or x is a negative
her first speed was 8 mph
her return speed was 24 mph
check:
6/8 + 6/24 = 1 , that's good!
1). A population of 20 rabbits is released into a wildlife region. The population is growing at a rate of 60% per year.
A) the General Equation from the Video was: P(x) = (blank)
What is the population of rabbits after 5 years?
B) the Evaluated equation I used to get the following answer is (blank)
and After five years there will be(blank)
rabbits.
And What is the population of rabbits after 8 years?
c) the Evaluated equation I used to get the following answer is(blank)
and After eight years there will be(blank)
rabbits.
Answer:
(a) A = 20(1.6)^t
(b) 210 rabbits
Step-by-step explanation:
Initial number of rabbits = 20
rate of growth, R = 60 % annually
(A) The general equation is
[tex]A = P \left ( 1+\frac{R}{100} \right )^t\\\\A = 20\left ( 1+\frac{60}{100} \right )^t\\\\A = 20 (1.6)^t[/tex]
(B) Let the time, t = 5 years
So, the population after 5 years is
[tex]A = 20 (1.6)^5\\\\A = 209.7 = 210 rabbits[/tex]
if x can be divide by 7 and 9 without leaving a remainder, it can also divided by which number without leaving a remainder
Answer:
all counting numbers except one
Given: x + 2 < -5.
Choose the solution set.
{x | x R, x < -3}
{x | x R, x < 3}
{x | x R, x < -7}
{x | x R, x < 7}
Answer:
C
Step-by-step explanation:
x + 2 < -5
x < - 5 - 2
x < - 7
Answer:
{x| x R, x<-7}
Step-by-step explanation:
=> x+2<-5
=> x<-5-2
=> x<-7
HELPP
-1-3(5m+8) ≥-85
i need help :D
Answer:
- 1 - 3(5m + 8) ≥ -85
-1 - 15m - 24 ≥ -85
-15m ≥ -85 + 1 + 24
-15m ≥ 25 - 85
-15m ≥ -60
(-1)(-15)m ≤ -60(-1)
15m ≤ 60
m ≤ 4
Which function is the result of translating f(x)=x^2+14 to the right 5 units and down 6 units
State the final conclusion in simple nontechnical terms.
Original claim: The proportion of male golfers is less than 0.6.
Initial conclusion: Fail to reject the null hypothesis.
Which of the following is the correct conclusion?
A. There is suffficient evidence to support the claim that the proportion of male golfers is less than 0.6.
B. There is not sufficient evidence to support the claim that the proportion of male golfers is less than 0.6.
Answer:
B. There is not sufficient evidence to support the claim that the proportion of male golfers is less than 0.6.
Step-by-step explanation:
The proportion of male golfers is less than 0.6.
At the null hypothesis, we test if the proportion is of at least 0.6, that is:
[tex]H_0: p \geq 0.6[/tex]
At the alternative hypothesis, we test if the proportion is of less than 0.6, that is:
[tex]H_1: p < 0.6[/tex]
Fail to reject the null hypothesis.
This means that there is not sufficient evidence to conclude that the proportion is less than 0.6, and thus the correct answer is given by option B.
Which of the following must be equal to 30% of x?
3x
(A)
1,000
3x
(B)
100
3x
(C)
10
(D) 3x
Answer:
You can go ahead with option D
Step-by-step explanation:
30% of x will be 3xTwo cities,a and are mapped on the coordinate plane. How far apart are they from each other?
Answer:
[tex]\sqrt{97} \\ \sqrt{9^{2}+4^{2} }[/tex]
Step-by-step explanation:
(4 + 4i)/(5+4i) = divide
Answer:
B.
Step-by-step explanation:
[tex] \frac{4 + 4i}{5 + 4i} [/tex]
Multiplying both numerator and denominator by (5 - 4i) , the conjugate of the denominator, i. e, (5 + 4i).[tex] \frac{4 + 4i}{5 + 4i} \times \frac{5 - 4i}{5-4i} [/tex]
[tex] \frac{(4 + 4i)(5 - 4i)}{(5 + 4i)(5 - 4i)} [/tex]
Multiplying (4+4i) and (5-4i) using distributive propertyUsing the identity (a+b)(a-b)= a² - b² where 5 will act as a and 4i will act as b[tex] \frac{20-16i+20i-16i^2}{(5) {}^{2} - (4i) {}^{2} } [/tex]
i² = -1(combining like terms)
[tex] \frac{20+(-16i+20i)-(-16)}{25-(-16)} [/tex]
[tex] \frac{(20+16)+4i}{25+16} [/tex]
[tex] \frac{36+4i}{41} [/tex]
distributing the denominator
[tex] \frac{36}{41} + \frac{4}{41}i [/tex]
That is, option B.
what is the equation of the directx for the following parabola -8(x-5)=(y+1)^2
Answer:
x=7
Step-by-step explanation:
The directrix of a parabola is the vertical line found by subtracting
p from the x-coordinate h
of the vertex if the parabola opens left or right.
x=h-p
Substitute the known values of
p and h
into the formula and simplify.
x=7
Find the values of x for which the denominator is equal to zero for y=x^2/x^2+1 .
Answer:
Step-by-step explanation:
I assume that you mean y = x²/(x²+1), not y = x²/x²+1.
x²+1 = 0
x² = -1
x = ±√(-1) = ±i
deleted: deleted by user
Please help
A stamp collection consists of 10 albums each containing 42 pages. How many stamps are in the total collection if 40 stamps fit on a page?
(1) 92
(2) 820
(3) 1,680
(4) 2,080
(5) 16,800
Step-by-step explanation:
Total number of albums = 10 albums[tex] \; [/tex]Number of pages in each album = 42 pages Stamps fit on 1 page = 40 stampsAs total number of pages in each album is 42 pages, so
➝ Total number of pages in 10 albums = (42 × 10) pages
➝ Total number of pages in 10 albums = 420 pages
Now, as the number of stamps fit on 1 page is 40 stamps, so
➝ Stamps fit on 420 pages = (420 × 40) stamps
➝ Stamps fit on 420 pages = 16,800 stamps
Therefore, 16,800 stamps are in the total collection.
On Monday, Ray had $153.75 in his bank account. On Tuesday, he withdrew $71.00 from his account. After depositing #292.50 on Wednesday, how much money did Ray have in his account
Answer:
$375.25
Step-by-step explanation:
[tex]===========================================[/tex]
Withdrew- taking out money (-)
Deposit- putting in money (+)
[tex]===========================================[/tex]
Ray started off with 153.75. He withdraws (-) 71.
[tex]153.75-71=82.75[/tex]
Then he deposits (+) 292.5.
[tex]82.75+292.5=375.25[/tex]
That's your answer!
I hope this helps ❤
Find the domain and range of the relation
Answer:
The domain is "all real numbers" and the range is x more than -3
There are 16 tablespoons in one cup. Which table correctly relates the number of cups to the number of tablespoons?
Answer:
The first table.
Step-by-step explanation:
1 cup = 1 * 16 = 16 tablespoons
2 = 2 * 16 = 32
3 = 3*16 = 48
4 = 4*16 = 64 and so on....
I need help with three
Answer:
A and F
Step-by-step explanation:
A and F both represent instances of division of 14/5
B represent multiplication
C represent the reciprocal of the problem, 5/14
D represent addition
Create your own proportion problems?
Answer:
See Explanation
Step-by-step explanation:
Required
Proportion problems
An example is:
y is directly proportional to x such that: y=4 when x = 2;
Derive the equation
For direct proportions, we have:
[tex]y\ \alpha\ x[/tex]
This gives:
[tex]y = kx[/tex]
Make k the subject
[tex]k = y/x[/tex]
So:
[tex]k = 4/2 =2[/tex]
So, the equation is:
[tex]y = kx[/tex]
[tex]y = 2x[/tex]
Assume the above question is for inverse proportion
The variation will be:
[tex]y\ \alpha\ \frac{1}{x}[/tex]
This gives:
[tex]y\ = \frac{k}{x}[/tex]
Make k the subject
[tex]k =x*y[/tex]
[tex]k =2* 4 = 8[/tex]
So, the equation is:
[tex]y\ = \frac{k}{x}[/tex]
[tex]y = \frac{8}{x}[/tex]
What is the ninth term in the binomial expansion of (x – 2y)13?
329,472x5y8
–329,472x5y8
–41,184x8y5
41,184x8y5
Answer:
It's A
Step-by-step explanation:
On Edg
Which statements apply to the expression
? Check all that apply.
3
The base is 5
The base is 3.
The exponent is 3.
3 3 3
The expanded form is 555.
3.3.3
The expanded form is
5
Answer:
A, C, D, F
Step-by-step explanation:
Given the expression : (3/5)³
Recall :
a^b where, a = base ; b = exponent
In ; (3/5)^3
Base = 3/5 ; exponent = 3
Similarly ;
a^b = a in b places
(3/5)^3 = (3/5) * (3/5) * (3/5)
(3/5) * (3/5) * (3/5) = (3*3*3) / (5*5*5) = 27/125
Hence, A, C, D and F are all correct