Answer:
(4,11/2)
Step-by-step explanation:
5x-2y=9
12x-8y=4
A quick look will tell us that neither the x- nor the y- coefficient is the same in both equations, so combining the two by addition or subtraction. We can see that 2 is a multiple of 8, since 2 x 4 = 8. We should multiply the first equation by 4.
4(5x-2y=9)
Now we need to decide if we should add or subtract the equations.
20x-8y=36
12x-8y=4
Since we need to have a -8 and a +8 to eliminate the variables, we should subtract them. Change all the signs of the second equation and combine.
20x-8y=36
-12x-8y=4
----------------
8x=32
Divide both sides by 8 to get the x-value:
[tex]\frac{8x}{8} = \frac{32}{8}[/tex]
x=4
Now that we have our x-value, we need to plug in the y-value.
5x-2y=9
5(4)-2y=9
20-2y=9
-2y=-11
y=11/2
So our solution is (4,11/2)
Let's check our work.
5x-2y=9
5(4)-2(11/2)=9
20-22/2=9
20-11=9
9=9
12x-8y=4
12(4)-8(11/2)=4
48-88/2=4
48-44=4
4=4
Our solution is correct.
Answer:
x=4,y=11/2
Step-by-step explanation:
5x−2y=9
12x−8y=4
In order to solve by elimination, coefficients of one of the variables must be the same in both equations so that the variable will cancel out when one equation is subtracted from the other.
5x−2y=9,12x−8y=4
To make 5x and 12x equal, multiply all terms on each side of the first equation by 12 and all terms on each side of the second by 5.
12×5x+12(−2)y=12×9,5×12x+5(−8)y=5×4
Simplify.
60x−24y=108,60x−40y=20
Subtract 60x−40y=20 from 60x−24y=108 by subtracting like terms on each side of the equal sign.
60x−60x−24y+40y=108−20
Add 60x to −60x. Terms 60x and −60x cancel out, leaving an equation with only one variable that can be solved.
−24y+40y=108−20
Add −24y to 40y.
16y=108−20
Add 108 to −20.
16y=88
Divide both sides by 16.
y=11/2
Substitute 11/2 for y in 12x−8y=4. Because the resulting equation contains only one variable, you can solve for x directly.
12x−8x11/2=4
Multiply −8 times 11/2.
12x−44=4
Add 44 to both sides of the equation.
12x=48
Divide both sides by 12.
x=4
The system is now solved.
x=4,y=11/2
Which of the fractions is equivalent to 2/5?
Answer:
4/10, 6/15, 8/20, 10/25
Step-by-step explanation:
"An education researcher recorded the number of books students read over the last year and the number of vocabulary words that students defined correctly on a test of 100 vocabulary words. The resulting data were used to conduct a hypothesis test to investigate whether there is a positive linear relationship between the number of books read and the number of vocabulary words defined correctly. What are the correct hypotheses for the test?"
Answer:
B
Step-by-step explanation:
help lol i can’t do math and everything is due at midnight
PLEASE ANSWER ASAP DUE IN 2 MIN WILL GIVE BRAINLEST!!!!!!!!!!!!!!!!
PLEASE ONLY ANSWER PART B
Answer:
because cfd eaquls a+b lllllllllll
Answer:
Step-by-step explanation:
IT is either the same as 7x+4 because it is infront of each other or you add 8x+6 and 6x+2 then you substract that from 180 to find out the remaining angle. Of course you have to subtitute the amount of x first.
6. cory gets paid every two weeks. he works 40 hours per week at $7.75 per hour. cory has the following deductions: 8% for medical insurance, 12% for federal and state taxes, and 10% for retirement. cory's net pay will be $________.
Answer:
$434
Step-by-step explanation:
Gross Pay
$7.75 per hour40 hours per weekPay received every 2 weeks⇒ Total gross pay = 7.75 × 40 × 2 = $620
Deductions
Medical insurance = 8%Taxes = 12%Retirement = 10%⇒ Total deductions = 8% + 12% + 10% = 30%
Net Pay
Net Pay = Total Gross Pay - Total deductions
= $620 - (30% of $620)
= $620 - (0.3 × $620)
= $620 - $186
= $434
Therefore, Cory's net pay will be $434.
Solve for 0 Round your answer to the nearest tenth.
20
13
A =
degrees
Answer:
1.835
Step-by-step explanation:
use pythagoras theorem to find missing side
use sin to find missing angle
missing side/13 = 1.835
3. P343. 13. A sociologist is interested in surveying workers in computer-related jobs to estimate the proportion of such workers who has changed jobs within the past years. (a) In the absence of preliminary data, how large a sample must be taken to ensure that a 95% confidence interval will specify the proportion to within ±0.05? (b) In a sample of 100 workers, 20 of them had changed jobs within the past year. Find a 95% confidence interval for the proportion of workers who have changed jobs within the past year. (c) Based on the data in part (b), estimate the sample size needed so that the 95% confidence interval will specify the proportion to within ±0.05.
Answer:
a) A sample of 385 must be taken.
b) The 95% confidence interval for the proportion of workers who have changed jobs within the past year is (0.1216, 0.2784).
c) A sample of 246 is needed.
Step-by-step explanation:
Question a:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
Absence of preliminary data:
This means that we use [tex]\pi = 0.5[/tex], which is when the largest sample will be needed.
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
How large a sample must be taken to ensure that a 95% confidence interval will specify the proportion to within ±0.05?
A sample of n must be taken.
n is found when [tex]M = 0.05[/tex]. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.05 = 1.96\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.05\sqrt{n} = 1.96*0.5[/tex]
Dividing both sides by 0.05
[tex]\sqrt{n} = 1.96*10[/tex]
[tex](\sqrt{n})^2 = (19.6)^2[/tex]
[tex]n = 384.16[/tex]
Rounding up,
A sample of 385 must be taken.
Question b:
In a sample of 100 workers, 20 of them had changed jobs within the past year.
This means that [tex]n = 100, \pi = \frac{20}{100} = 0.2[/tex]
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2 - 1.96\sqrt{\frac{0.2*0.8}{100}} = 0.1216[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2 + 1.96\sqrt{\frac{0.2*0.8}{100}} = 0.2784[/tex]
The 95% confidence interval for the proportion of workers who have changed jobs within the past year is (0.1216, 0.2784).
Question c:
Same procedure as question a, just with [tex]\pi = 0.2[/tex]
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.05 = 1.96\sqrt{\frac{0.2*0.8}{n}}[/tex]
[tex]0.05\sqrt{n} = 1.96\sqrt{0.2*0.8}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.2*0.8}}{0.05}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96\sqrt{0.2*0.8}}{0.05})^2[/tex]
[tex]n = 245.8[/tex]
Rounding up
A sample of 246 is needed.
Simplify 42 ⋅ 48.
Please help with this!
Answer:
Step-by-step explanation:
a^x. a^y=a^{x+y}
4²*4^8=4^{10}
Answer:
4 to the power of 10
Step-by-step explanation:
The area of a circle is 4 square centimeters. What is the circumference?
HELP DUE IN 2 MINUTESS!!!! PLS HELP
An Urn contains 6 red marbles and 9 white marbles. A marble is drawn and put back into the urn. Both marbles were red. If another marble is drawn, what is the probability of it being white?
Answer:
3/5
Step-by-step explanation:
favorable outcomes/total number of outcomes=probability
Answer:
[tex] \frac{3}{5} [/tex]
Step-by-step explanation:
Previous extractions do not influence the probability
c. Translate the follom
4.) 51 - (x+5)
5.) 3(7-8)
Step-by-step explanation:
1. 51-x-5
= 46-x Answer
2. 21-24
= -3 Answer
Using the following data, calculate the mean absolute deviation: 7 2 8 5 9 9 5 6 8 1 What is the mean absolute deviation for these data? (4 points)
Answer:
The mean absolute deviation is 2. Hope this helps
Step-by-step explanation:
7+2+8+9+9+5+6+8+1=5.5
7-5.5=1.5
5.5-2=3.5
8-5.5=2.5
9-5.5=3.5
9-5.5=3.5
5.5-5=0.5
6-5.5=1.5
8-5.5 2.5
5.5-1=4.5
1.5+3.5+2.5+3.5+3.5+0.5+1.5+2.5+4.5=2
Answer is 2.
I hope this can help!
Have a nice day :)
~Amy
NEED HELP ASAP WILL GIVE BRAINLIEST REAL ANSWERS ONLY PLZ
Answer:
D
Step-by-step explanation:
They are trying to see how long it takes people to complete the writing portion of the test.
A retiree invests $7,000 in a savings plan that pays 7% per year. What will the account balance be at
the end of the first year?
Answer:
$6510
Step-by-step explanation:
First thing that should come to mind is: What is 7% of $7000?
Well, if you don't know how to find a percent of something, this is the formula you use:
7000 x 0.07 = 490.
In the first year, they will receive 490 out of the 7000 they've invested.
7000 - 490 = 6510.
Therefore, the account balance at the end of the first year will be 6510.
The account balance at the end of first year will be equal to $6510.
What do you mean by percentage ?
Percentage is the relative value indicating one hundredth part of any quantity.
It is given that a retiree invests $7000 in a savings plan which pays 7% per year. So , it meant that we need to calculate that what is the value 7% of $7000.
So , 7% of $7000 is :
= 7000 × [tex]\frac{7}{100}[/tex]
= $490
It is known that this amount is paid as per plan per year. So, to find out the account balance at the end of the first year , we need to subtract the invested amount to the amount per year at 7%.
So , the account balance at the end of first year will be :
= 7000 - 490
= $6510
Therefore , the account balance at the end of first year will be equal to $6510.
Learn more about percentage here :
brainly.com/question/22091903
#SPJ2
Il means
* is equal to
* is parallel to
*lines
* therefore
* none of these
BRAINLIEST FOR ALL 3 CORRECT ANSWERS, IM FAILING SCHOOL AND NEED HELP ASAP. EVEN OFFICIAL HELP COUNTS
Answer:
1. quarter turn 2. B 3. (b,-a)
Step-by-step explanation:
If the rate of change of the graph of a linear equation is 4 and the y-intercept is (0, 8), what is the linear equation that represents the graph?
Answer:
y = 4x + 8
Step-by-step explanation:
The linear equation can be written in the form y = mx + b. "y" and "x" stay as they are. The "m" is the slope or rate of change. The b is the y-intercept.
Hope it helps!!!
(May I have brainliest if it's correct please?)
Question 6 of 10 What is the slope of the line that contains the points (-2, 2) and (3, 4)? O A. 01N B. 5 C. 5 2 D. 2 SUBMIT
Answer:
I don't know what those answer choices are but the answer should be: [tex]\frac{2}{5}[/tex]
Step-by-step explanation:
4-2 = 2
3 - (-2) = 5
Put the y values over the x
[tex]\frac{2}{5}[/tex]
solve the system of linear equations by elimination. 6x-4y=18 3x+2y=-3
Answer:
y = -3
x = 1
Step-by-step explanation:
6x-4y=18
3x+2y=-3, so 3x = -2y - 3, then x = (-2y - 3)/3
substitute for x:
6((-2y - 3)/3) - 4y = 18
2(-2y - 3) - 4y = 18
-4y - 6 - 4y = 18
-8y - 6 = 18
-8y = 24
y = -3
x = (-2(-3) -3)/3 = 1
A car rental company is interested in the amount of time its vehicles are out of operation for repair work. A random sample of 21 cars showed that, over the past year, the numbers of days that each of these cars had been inoperative were as follows: 15, 11, 19, 24, 6, 18, 20, 15, 18, 12, 14, 19, 5, 21, 12, 11, 8, 10, 7, 2, 14 Assuming that the population is normally distributed, construct a 95% confidence interval for the mean number of days that vehicles in the company's fleet are out of operation.
Answer:
(10.891; 15.869)
Step-by-step explanation:
Given the data::
15, 11, 19, 24, 6, 18, 20, 15, 18, 12, 14, 19, 5, 21, 12, 11, 8, 10, 7, 2, 14
The confidence interval is obtained using the relation :
Mean ± margin of error
Margin of Error = Zcritical * s/sqrt(n)
Using a calculator, the mean value of the data and standard deviation above is :
Mean = Σx / n ; n = sample size
Mean, xbar = 281 / 21
Mean = 13.38
Standard deviation , s = sqrt[Σ(X - xbar)²/ n-1]
Standard deviation, s = 5.82
Margin of Error = Zcritical * s/sqrt(n)
Zcritical at 95% confidence level = 1.96
Margin of Error = 1.96 * 5.82/sqrt(21) = 2.489
Confidence interval :
Mean ± margin of error
13.38 ± 2.489
Lower boundary = (13.38 - 2.489) = 10.891
Upper boundary = (13.38 + 2.489) = 15.869
(10.891; 15.869)
A spinner has six equal-sized sections numbered 1, 1, 2, 2, 3, and 4. What is the probability of spinning a 3?
Answer:
1/6 or 0.166666...
Step-by-step explanation:
1 out of 6, so 1/6
Two of the angles in a triangle measure 90 degrees and 7 degrees what is the measure of the third angle
Answer:
The third angle would be 83 degrees.
Step-by-step explanation:
Seeing that every triangle's angles will always add up to 180 degrees, we would do the following:
180-90=90
90-7=83 degrees.
Which is the graph of x - y = 1?
y
y
5
5
4
4
3
3
3
2
2
2
1
1
4
3
1 2
5
5
4-3-2-1,
1 2 3 4 5 X
4
1 2 3
5-4-3-2-11
5-4-3-2-1
2
-2
2-
-3
3
4
4
5
5
ly
5
4
3
Answer:
the 3rd graph
Step-by-step explanation:
The graph which represents x-y = 1 is; The 3rd graph.
Graph of a straight lineFrom the task content, the given equation of the line is; x - y = 1.
By rearranging the equation to take the slope-intercept form;.
y = x - 1.Hence, slope of the graph is 1 and the y-intercept of the graph is -1.
On this note, only the 3rd graph satisfies the conditions above.
Read more on graph of a straight line;
https://brainly.com/question/14323743
Please please help please
Answer:
Greater Than [The second choice]
Step-by-step explanation:
Factor by removing a common
1. 3a +9ab
Answer:
3a(1+3b)
Step-by-step explanation:
First step is to find the greatest common factor between these two terms, which is 3a. Next you'll need to divide the two terms by that factor, which would give you what would be in the parenthesis, placed the factor in front to signify the multiplication of those terms and voila, you got the fully factored form.
-7x+4y=32
-5x-2y = -16
elimination method explain please
Answer:
(0,8)
Step-by-step explanation:
-7x+4y=32
-10x-4y=-32
-17x=0
x=0
-5×0-2y=-16
y=8
(0,8)
1 Which expression can be used to find the volume, in cubic centimeters, of the solid shown? Choose all that apply. 3 cm 4 cm 7 cm 5 cm 9 cm A (3 X 4 X 5) + (3 X 5 X 9) B (3 X 5 X 6) + (5 X 4 X 3) C (9 X 5 X 3) + (3 X 5 X 7) D (7 X 5 X 3) + (6 X 5 X 3) E (3 X4 X 7) + (6 X 5 X 4)
Answer:
I think its D
Step-by-step explanation:
What is the range of y=4sin(x)-2
Answer:
According to me it should be -6 [tex]\leq[/tex] y [tex]\leq[/tex] 2.
Step-by-step explanation:
The cost of 12 oranges and 7 apples is 5.36. Eight oranges and 5 apples cost 3.68. Find the cost of each
Which sign makes this number sentence true?
|-6| __ |6|
A. >
B. <
C. =
D.
Answer:
C. =
Step-by-step explanation:
whenever you have | | It will always be positive so -6 turns to 6 and that makes it equal.