Answer:
1) Parallel lines are "ALWAYS"
coplanar.
2) Perpendicular lines ARE "ALWAYS"
coplanar.
3) Distance around an unmarked circle CAN "NEVER" be measured
Step-by-step explanation:
1) Coplanar means lines that lie in the same plane. Now, for a line to be parallel to another line, it must lie in the same plane as the other line otherwise it is no longer a parallel line. Thus, parallel lines are always Coplanar.
2) similar to point 1 above, perpendicular lines are Coplanar. This is because perpendicular lines intersect each other at right angles and it means they must exist in the same plane for that to happen. Thus, they are always Coplanar.
3) to have the distance, we need to have the circle marked out. Because it is from the marked out circle that we can measure radius, diameter and find other distances around the circle. Thus, distance around an unmarked circle can never be measured.
Evaluate these questions 27(1/3)2
Answer:
18
Step-by-step explanation:
1/3 of 27 is 9. 9 times 2 is 18.
Please help me i will give you brainly please
Answer:
19. 3x+5/2x+7 =5
or, 3x+5=5×(2x + 7)
or, 3x + 5 = 10x + 35
or, 5 - 35 = 10x - 3x
or, -30 = 7x
or, -30/7 = x
21. let x be the other number
we know,
or, x × 1/7 =2
or, x/7 =2
or, x = 14
therefore, the other number is 14.
How can one estimate a car annual fuel expense
Answer:
determine the number of miles the car drives in a year.
divide that number by the cars average MPG (miles per gallon) then multiply that number by the average cost of a gallon of gas in your area.
Step-by-step explanation:
Prove that: (secA-cosec A) (1+cot A +tan A) =( sec^2A/cosecA)-(Cosec^2A/secA)
Step-by-step explanation:
[tex](\sec A - \csc A)(1 + \cot A + \tan A)[/tex]
[tex]=(\sec A - \csc A)\left(1 + \dfrac{\cos A}{\sin A} + \dfrac{\sin A}{\cos A} \right)[/tex]
[tex]=(\sec A - \csc A)\left(1 + \dfrac{\cos^2 A + \sin^2 A}{\sin A\cos A} \right)[/tex]
[tex]=(\sec A - \csc A)\left(\dfrac{1 + \sin A \cos A}{\sin A \cos A} \right)[/tex]
[tex]=\left(\dfrac{\frac{1}{\cos A} - \frac{1}{\sin A}+\sin A - \cos A}{\sin A\cos A}\right)[/tex]
[tex]=\dfrac{\sin A - \sin A \cos^2A - \cos A + \cos A\sin^2A}{(\sin A\cos A)^2}[/tex]
[tex]=\dfrac{\sin A(1 - \cos^2A) - \cos A (1 - \sin^2 A)}{(\sin A\cos A)^2}[/tex]
[tex]=\dfrac{\sin^3A - \cos^3A}{\sin^2A\cos^2A}[/tex]
[tex]=\dfrac{\sin A}{\cos^2A} - \dfrac{\cos A}{\sin^2A}[/tex]
[tex]=\left(\dfrac{1}{\cos A}\right)\left(\dfrac{\sin A}{1}\right) - \left(\dfrac{1}{\sin^2A}\right) \left(\dfrac{\cos A}{1}\right)[/tex]
[tex]=\sec^2A\csc A - \csc^2A\sec A[/tex]
Three more than twice a number is 35.
Answer:
x = 16, or if you didn't want the value for x,
2x + 3 = 35
Step-by-step explanation:
Three more: +3
Twice a number: 2x
Combined:
2x + 3 = 35.
Get rid of the 3 by subtracting it from both sides:
2x = 32
Get rid of the 2 by dividing it from both sides:
x = 16
Answer:
The number is 16.
Step-by-step explanation:
Let the unknown number be x.
Now we translate the sentence into an equation piece by piece.
Three more than twice a number is 35.
2x
Three more than twice a number is 35.
2x + 3
Three more than twice a number is 35.
2x + 3 = 35
Now we solve the equation.
Subtract 3 from both sides.
2x = 32
Divide both sides by 2.
x = 16
Answer: The number is 16.
P.S. Notice that x was a variable that was introduced solely to solve the problem. The original problem is a word problem, not an equation, and has no x in it. The correct answer makes no reference to x since x was used to solve the equation but is not part of the given problem. The person asking the question has no idea what x is. He just wants a number as an answer.
Meghan sells advertisements for a radio station. Each 30 second ad costs $20 per play, and each 60 second ad
costs $35 per play. Meghan sold 12 ads for $315. She wrote the system below letting x represent the number of 30
second ads and y represent the number of 60 second ads.
X+ y = 12
20x+35y = 315
What is the solution to the system of equations?
Need answers ASAP!!!!
Answer:
usai964s46s694s4o6s64694s946649s469 opps
Answer:
[tex](x,y)=(7,5)[/tex]
Step-by-step explanation:
Megan's equation will be:
[tex]20x+35y=315[/tex]
[tex]x+y=12[/tex]
Substitute [tex]x=12-y[/tex] in the first equation:
[tex]20(12-y)+35y=315[/tex]
[tex]15y=75[/tex]
[tex]y=75/15[/tex]
[tex]y=5[/tex]
Find x:
[tex]x=12-5[/tex]
[tex]x=7[/tex]
Where x and y represent 30-second and 60-second ads sold, we find that Meghan's sales were:
[tex](x,y)=(7,5)[/tex]
hope this helps....
A jar contains 4 pieces of gum, 7 pieces of candy, and 3 pieces of mint. Each time you draw out an item, you record the outcome and put the item back in the jar before making another draw. What is the probability that you get exactly the following sequence: candy—mintmcandy, in that order?
(a) 0.0300.
(b) 0.0530.
(c) 0.1607.
(d) 1.2143.
Answer:
The correct answer is B.
Step-by-step explanation:
Since a jar contains 4 pieces of gum, 7 pieces of candy, and 3 pieces of mint, and each time you draw out an item, you record the outcome and put the item back in the jar before making another draw, to determine what is the probability that you get exactly the sequence candy-mint-candy, in that order, the following calculation should be performed:
4 + 7 + 3 = 14
7/14 x 3/14 x 7/14 = X
0.5 x 0.2142 x 0.5 = X
0.053 = X
Therefore, the probability that the chosen sequence will be obtained is 0.0530, or 5.3%.
We are testing a new drug with potentially dangerous side effects to see if it is significantly better than the drug currently in use. If it is found to be more effective, it will be prescribed to millions of people.
1.
a. What does it mean in context to make a type I error in this situation?
b. What does it mean in context to make a type Il error in this situation?
c. Which error do you think is worse? Now we are testing to see whether taking a vitamin supplement each day has significant health benefits. There are no (known) harmful side effects of the supplement.
2.
a. What does it mean in context to make a type I error in this situation?
b. What does it mean in context to make a type Il error in this situation?
c. Which error do you think is worse? For a given situation, what should you do if you think that committing a type l error is much worse than committing a type Il error?
A. Increase the significance level.
B. Decrease the significance level.
C. Nothing, just be careful to take a good sample.
Answer:
1) a) accepting the new drug is better based on its effectiveness when in reality the drug ain't better than the drug in current use because of its side effects
b) Accepting and using the current drug in use when it is not as effective as the new drug
c) Type 1 error
2) a) rejecting the vitamin supplement based on not knowing the harmful side effects
b) Accepting the Vitamin supplement based on just health benefits it portrays without comparison with other supplement.
c) Type II error
3) Increase the significance level ( A )
Step-by-step explanation:
1)
a) To make a type 1 error in this situation is accepting the new drug is better and prescribing it to the millions of people based only on its effectiveness when in reality the drug ain't better than the drug in current use because of its side effects
b) A type II error in context is :Accepting and using the current drug in use when it is not as effective as the new drug
c) Type I error
2)
a) Type 1 error is rejecting the vitamin supplement based on not knowing the harmful side effects
b) Accepting the Vitamin supplement based on just health benefits it portrays without comparison with other supplement.
c) Type II error
3) If committing a type 1 error is much worse
Increase the significance level
Roulette is a casino game that involves spinning a ball on a wheel that is marked with numbered squares that are red, black, or green. Half of the numbers 1 - 36 are colored red and half are black and the numbers 0 and 00 are green. Each number occurs only once on the wheel. What is the probability of landing on an even number and a number greater than 17? (A number is even if it is divisible by 2. 0 and 00 are considered even as well.)
Answer:
the wording (punctuation) of the question can lead to different interpretations....
I assume that the question was >17 & even which is "5/19",
BUT... it can also be read as two questions
first >17 which is "10/19"
and second an even number which is "9/19"
BUT !!! I think that the question answer is 5/19
Step-by-step explanation:
Even Number = 18/38 = 9/19
greater 17 = 20/38 = 10/19
Even & greater 17 = 10/38 = 5/19
Escreva a matriz A = (aij) do tipo 3x4 sabendo que aij = 3i – 2j.
Answer:
[tex]A = \left[\begin{array}{cccc}1&-1&-3&-5\\4&2&0&-2\\7&5&3&1\end{array}\right][/tex]
Step-by-step explanation:
A = (aij)
i representa a linha e j a coluna.
Tipo 3x4
Isto implica que a matriz tem 3 linhas e 4 colunas.
aij = 3i – 2j.
Primeira linha:
[tex]a_{1,1} = 3(1) - 2(1) = 1[/tex]
[tex]a_{1,2} = 3(1) - 2(2) = -1[/tex]
[tex]a_{1,3} = 3(1) - 2(3) = -3[/tex]
[tex]a_{1,4} = 3(1) - 2(4) = -5[/tex]
Segunda linha:
[tex]a_{2,1} = 3(2) - 2(1) = 4[/tex]
[tex]a_{2,2} = 3(2) - 2(2) = 2[/tex]
[tex]a_{2,3} = 3(2) - 2(3) = 0[/tex]
[tex]a_{2,4} = 3(2) - 2(4) = -2[/tex]
Terceira linha:
[tex]a_{3,1} = 3(3) - 2(1) = 7[/tex]
[tex]a_{3,2} = 3(3) - 2(2) = 5[/tex]
[tex]a_{3,3} = 3(3) - 2(3) = 3[/tex]
[tex]a_{3,4} = 3(3) - 2(4) = 1[/tex]
Matriz:
A matriz é dada por:
[tex]A = \left[\begin{array}{cccc}1&-1&-3&-5\\4&2&0&-2\\7&5&3&1\end{array}\right][/tex]
Find the solution set.
The solution set for 5v2 – 125 = 0
Find the missing term in the pattern.
Answer:
20
Step-by-step explanation:
Find the value of z, the measure of the subtended arc.
86°
47°
188°
94°
Answer:
188 degrees
Step-by-step explanation:
The measure of the arc is the center angle, that is double of the circumference one
94 * 2 = 188 degrees
A car and a motorcycle whose average rates are in the ratio of 4:5 travel a distance of 160 miles. If the motorcycle
travels 1/2 hour less than the car, find the average rate of each.
Answer:
Step-by-step explanation:
I always advise my students to make a table of information for these story problems because trying to keep track of the information otherwise is a nightmare. The table will look like this:
d = r * t
m
c
m is motorcycle and c is car.
First thing we are told is that the ratio of m's speed to c's speed is 5:4; that means that we can divide 5/4 to find out how many times faster m is going than c.
5/4 = 1.25 so we have a couple of values to put into the table right away, along with the fact that they are both traveling the same distance of 160 miles.
d = r * t
m 160 = 1.25r
c 160 = r
The last thing we have to fill in is the time. If m travels a half hour less than c, c is driving a half hour more than m, right? Filling that in:
d = r * t
m 160 = 1.25r * t
c 160 = r * t + .5
Now we have our 2 equations. Looking at the top row of the table gives us the formula we need to solve this problem. It tells us, in other words, what we are going to be doing with these columns of numbers. Distance equals the rate times the time. For the motorcycle, the equation is:
160 = (1.25r)t and that seems pretty useless since we still have 2 unknowns in there and you can only have 1 unknown in 1 equation. Let's see what the equation for the car is.
160 = (t + .5)r Same problem.
Let's go back to the equation for the motorcycle and since we are looking for the rates of each, let's solve that equation for time in terms of rate (solve it for t):
[tex]t=\frac{160}{1.25r}[/tex] and sub that into the car's equation in place of t:
[tex]160=r(\frac{160}{1.25r})+.5r[/tex] and simplify. The r's to the left of the plus sign cancel out leaving us with:
[tex]160=(\frac{160}{1.25})+.5r[/tex] and divide those numbers inside the parenthesis to get:
160 = 128 + .5r and subtract 128 from both sides to get:
32 = .5r and finally divide by .5 to get
r = 64 miles/hour
The car goes 64 mph and the motorcycle goes 1.25 times that so,
m = 1.25(64) and
m = 80 mph
This exercise uses the population growth model. The population of a certain species of fish has a relative growth rate of 1.9% per year. It is estimated that the population in 2010 was 11 million. (a) Find an exponential model n(t)
Answer:
n(t) = 11e^0.019t
Step-by-step explanation:
The estimated population in 2010 = 11,000,000 = initial population
The growth rate = 1.9% per year = 1.9/100 =
The exponential growth model follows the general form :
n(t) = ae^rt
a = Initial population ; r = growth rate ; t = period
Hence, we have ;
n(t) = 11e^0.019t in millions
were should i go shopping for fidgets
Answer:
Amazon
Step-by-step explanation:
Atomic No.
Element
Atomic Wt.
Europium
To take a systematic sample, first choose any number between one and five and write it here: k-23
Using the atomic number to count off elements, let the k value you just chose represent the first element in your
sample. Then, count off every fifth element thereafter. For instance, if you chose k-2, your sample will include
Helium (2), Nitrogen (7), Magnesium (12), and so forth. List each atomic number and atomic weight, starting with k
and adding 5 to the atomic number cach time.
Atomic No. Element
Atomic Wt.
3. Lithium 6.94
63
Isla6
8
v४
16
oxygen
Erbium 167.26
13 nluminum 24.98 23 Tantalum
180.45
18 Argon
39.95
28
platinum
195.DK
23 Vanadium 50.94 83 Bismuth 208.48
Niin
28
86
158.69
Radium 226
33
Arsenic 74.92
93 Neptunium 237
38 Strontium
98
87.62
Californium 251
43 Technutium 98
103 Lawrencium 262
UR
cocaina [12.41
108
Hassium
277
Iodine 126.9
113
No element
o
658 Cerium 140:11 118 Unumactiun
63
294
Find the mean atomic weight of this sample and enter it here: x xytomate : 137
AP statistics
Answer:
Atomic No.
Element
Atomic Wt.
Europium
To take a systematic sample, first choose any number between one and five and write it here: k-23
Using the atomic number to count off elements, let the k value you just chose represent the first element in your
sample. Then, count off every fifth element thereafter. For instance, if you chose k-2, your sample will include
Helium (2), Nitrogen (7), Magnesium (12), and so forth. List each atomic number and atomic weight, starting with k
and adding 5 to the atomic number cach time.
Atomic No. Element
Atomic Wt.
3. Lithium 6.94
63
Isla6
8
v४
16
oxygen
Erbium 167.26
13 nluminum 24.98 23 Tantalum
180.45
18 Argon
39.95
28
platinum
195.DK
23 Vanadium 50.94 83 Bismuth 208.48
Niin
28
86
158.69
Radium 226
33
Arsenic 74.92
93 Neptunium 237
38 Strontium
98
87.62
Californium 251
43 Technutium 98
103 Lawrencium 262
UR
cocaina [12.41
108
Hassium
277
Iodine 126.9
113
No element
o
658 Cerium 140:11 118 Unumactiun
63
294
Find the mean atomic weight of this sample and enter it here: x xytomate : 137
AP statistics
Step-by-step explanation:
5x5+90
I honestly have no idea wth this answer is . Please help meeee
How many 10 digits numbers have no two digits the same and do not start with 0 or 1?
Answer:
at least 99
Step-by-step explanation:
each number starting from 2 can be moved 11 times per thing.
According to the graph above, College R showed
the greatest change in enrollment between which
two decades?
Given:
The graph that shows the ennoblement for college R between 1950 and 2000.
To find:
The two decades that has the greatest change in enrollment.
Solution:
From the given graph, it is clear that the change in the enrollment is:
From 1950 to 1960 is [tex]4-3.5=0.5[/tex] thousand.
From 1960 to 1970 is [tex]5-4.5=1.5[/tex] thousand.
From 1970 to 1980 is [tex]5.5-5=0.5[/tex] thousand.
From 1980 to 1990 is [tex]6.5-5.5=1[/tex] thousand.
From 1990 to 2000 is [tex]7-6.5=0.5[/tex] thousand.
The two decades 1960-1970 and 1980-1990 have the greatest change in enrollment.
Answer:1980 to 1990
Step-by-step explanation:
Which rule describes the transformation shown?
1. (x,y) → (-y, x+7)
2. (x,y) → (x+7,-y)
3. (x,y) → (-x, y+7)
4. (x,y) → (y+7, -x)
Answer:
2. (x,y) → (x+7,-y)
Step-by-step explanation:
Point A:
The original coordinate of point A was (-6,-6).
The coordinate after the transformation is A'(1,6), which eliminates option 3.
Point B:
The original coordinate of point B was (-2,4).
After the transformation, we have B'(5,-4), which eliminates option 1 and option 4. This means that the correct answer is:
2. (x,y) → (x+7,-y)
In the rhombus, mZ1 = 140. What are mZ2 and mZ3? The diagram is not to scale.
gjgb go ftc in the class is not a short time to be be free and ear is not a short time to
The width of a rectangle is 2 cm less than its length. The perimeter is 52 cm. The length is:
14 cm.
12 cm.
9 cm.
None of these choices are correct.
Answer: 14 cm
Step-by-step explanation:
Rectangle:
Length = xWidth = x - 2x + x + (x - 2) + (x - 2) = 52
2x + 2(x - 2) = 52
2x + 2x - 4 = 52
4x = 52 + 4
4x = 56
x = 14
Find the critical point for f and then use the second derivative test to decide whether the critical point is a relative maximum or a relative minimum.f(x)=-x^2-2x-9
Answer:the answer is 9
Step-by-step explanation:
aulo uses an instrument called a densitometer to check that he has the correct ink colour.
For this print job the acceptable range for the reading on the densitometer is 1.8 ± 10%.
What is the acceptable range for the densitometer reading?
Answer:
The range is from 1.62 to 1.98.
Step-by-step explanation:
We have to solve for the percentage of the particular value if the range of the answer should be +/- 10% of the particular value.
The value given is 1.8, we thus want to find 10% of that: 1.8 * 10/100 = 0.18
Then, add this value to the original value of 1.8: 1.8+0.18 = 1.98
Furthermore, subtract .18 from from the original value of 1.8: 1.8-0.18 = 1.62
The range will be between these two numbers, so the range is from 1.62 to 1.98.
The Power in a circuit is given by the formula P=I^{2}R, where I is the Current and R is the Resistance. If the Resistance is always constant at 500, the Current is 1, and dI/dt = -0.5, then dP/dt = -500.
True or false and please show work. Thank you
True
Step-by-step explanation:
[tex]P(t) = I^2(t)R[/tex]
Taking the derivative of P(t) with respect to time,
[tex]\dfrac{dP(t)}{dt} = 2I(t)\dfrac{dI(t)}{dt}R[/tex]
[tex]\:\:\:\:\:\:\:\:= 2(1)(-0.5)(500) = -500[/tex]
The following measurements (in picocuries per liter) were recorded by a set of argon gas detectors installed in a research facility:
381.3,394.8,396.1,380
Using these measurements, construct a 95% confidence interval for the mean level of argon gas present in the facility. Assume the population is approximately normal.
Answer:
The 95% confidence interval for the mean level of argon gas present in the facility is (374.4, 401.7).
Step-by-step explanation:
Before building the confidence interval, we have to find the sample mean and the sample standard deviation.
Sample mean:
[tex]\overline{x} = \frac{381.3+394.8+396.1+380}{4} = 388.05[/tex]
Sample standard deviation:
[tex]s = \sqrt{\frac{(381.3-388.05)^2+(394.8-388.05)^2+(396.1-388.05)^2+(380-388.05)^2}{3}} = 8.58[/tex]
Confidence interval:
We have the standard deviation for the sample, so the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 4 - 1 = 3
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 3 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 3.1824
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 3.1824\frac{8.58}{\sqrt{4}} = 13.65[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 388.05 - 13.65 = 374.4
The upper end of the interval is the sample mean added to M. So it is 388.05 + 13.65 = 401.7
The 95% confidence interval for the mean level of argon gas present in the facility is (374.4, 401.7).
Which of the following values cannot be probabilities? 3/5, 2, 0, 1, −0.45, 1.44, 0.05, 5/3 Select all the values that cannot be probabilities.
Given:
The numbers are [tex]\dfrac{3}{5},2,0,1,-0.45, 1.44[/tex].
To find:
All the values that cannot be probabilities.
Solution:
We know that,
[tex]\text{Probability}=\dfrac{\text{Favorable outcomes}}{\text{Total outcomes}}[/tex]
The minimum value of favorable outcomes is 0 and the maximum value is equal to the total outcomes. So, the value of probability lies between 0 and 1, inclusive. It other words, the probability lies in the interval [0,1].
[tex]0\leq \text{Probability}\leq 1[/tex]
From the given values only [tex]\dfrac{3}{5}, 0, 1[/tex] lie in the interval [0,1]. So, these values can be probabilities.
The values [tex]2,-0.45, 1.44[/tex] does not lie in the interval [0,1]. So, these values cannot be probabilities.
Therefore, the correct values are [tex]2,-0.45, 1.44[/tex].
A classmate walks into class and states that he has an extra ticket to a chamber orchestra concert on Friday night. He asks everyone in the class to put their name on a piece of paper and put it in a basket. He plans to draw from the basket to choose the person who will attend the concert with him. If there are 38 other people in class that night, what is your chance of being chosen to attend the concert
Answer:
2.56% chance of being selected
Step-by-step explanation:
Given
[tex]n = 39[/tex] --- you and 38 others
Required
Chance of you being selected
To do this, we simply calculate the probability using:
[tex]Pr(x) = \frac{n(x)}{n}[/tex]
Where:
[tex]n(x)= 1[/tex] --- i.e you are just 1 person
So:
[tex]Pr(x) = \frac{1}{39}[/tex]
[tex]Pr(x) = 0.0256[/tex]
Express as percentage
[tex]Pr(x) = 2.56\%[/tex]
LOOK AT THE BOTTOM PLEASE MAKE SURE YOU ARE RIGHT
Answer:
reflection
Step-by-step explanation:
B is the mirror image of A across a line between the two images
