Answer:
A. (5, 2)
Step-by-step explanation:
Given
[tex]\begin{cases}x+y=7,\\2x+3y=16\end{cases}[/tex],
Multiply the first equation by 2, then subtract both equations to get rid of any terms with [tex]x[/tex]:
[tex]\begin{cases}2(x+y)=2(7),\\2x+3y=16\end{cases}\\\implies 2x+2y=14,\\2x+3y=16,\\2x-2x+2y-3y=14-16,\\-y=-2,\\y=\boxed{2}[/tex]
Substitute [tex]y=2[/tex] into any equation to solve for [tex]x[/tex]:
[tex]x+y=7,\\x+2=7,\\x=7-2=\boxed{5}[/tex]
Since coordinates are written as (x, y), the solution to this system of equations is (5, 2).
Answer:
A. ( 5 , 2 )
Step-by-step explanation:
solve by elimination methodIn 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.
x + y = 7, 2x + 3y = 16To make x and 2x equal, multiply all terms on each side of the first equation by 2 and all terms on each side of the second by 1.
2x + 2y = 2 × 7, 2x + 3y = 16Simplify.
2x + 2y = 14, 2x+3y=16Subtract 2x+3y=16 from 2x+2y=14 by subtracting like terms on each side of the equal sign.
2x - 2x + 2y - 3y = 14 - 16Add 2x to -2x. Terms 2x and -2x cancel out, leaving an equation with only one variable that can be solved.
2y - 3y = 14 - 16Add 2y to -3y.
-y = 14 - 16Add 14 to -16.
-y = -2Divide both sides by -1.
y = 2Substitute 2 for y in 2x+3y=16. Because the resulting equation contains only one variable, you can solve for x directly.
2x + 3 × 2 = 16Multiply 3 and 2
2x + 6 = 16Subtract 6 from both sides of the equation.
2x = 10Divide both sides by 2.
x = 10The system is now solved.
x = 5 and y = 2
Two trains leave stations 192 miles apart at the same time and travel toward each other. One train travels at 85 miles per hour while the other travels at 75
miles per hour. How long will it take for the two trains to meet?
Do not do any rounding.
11 hours
Answer:
32 miles per hour
Step-by-step explanation:
x+85+75=192 x+160=192 x=192-160 x=32..
About 9% of the population has a particular genetic mutation. 900 people are randomly selected. Find the standard deviation for the number of people with the genetic mutation in such groups of 900.
Answer:
The standard deviation is of 8.586.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they have a genetic mutation, or they do not. The probability of a person having the mutation is independent of any other person, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
About 9% of the population has a particular genetic mutation.
This means that [tex]p = 0.09[/tex]
900 people are randomly selected.
This means that [tex]n = 900[/tex]
Find the standard deviation for the number of people with the genetic mutation in such groups of 900.
[tex]\sqrt{V(X)} = \sqrt{900*0.09*0.91} = 8.586[/tex]
The standard deviation is of 8.586.
You are given the following information about x and y.
x y Independent Dependent Variable Variable 15 5 12 7 10 9 7 11
The least squares estimate of b 0 equals ______.
a. 16.41176
b. â1.3
c. 21.4
d. â7.647
Answer:
[tex]b_0 = 16.471[/tex]
Step-by-step explanation:
Given
[tex]\begin{array}{ccccc}x & {15} & {12} & {10} & {7} \ \\ y & {5} & {7} & {9} & {11} \ \end{array}[/tex]
Required
The least square estimate [tex]b_0[/tex]
Calculate the mean of x
[tex]\bar x = \frac{\sum x}{n}[/tex]
[tex]\bar x = \frac{15+12+10+7}{4} =\frac{44}{4} = 11[/tex]
Calculate the mean of y
[tex]\bar y = \frac{\sum y}{n}[/tex]
[tex]\bar y = \frac{5+7+9+11}{4} =\frac{32}{4} = 8[/tex]
Calculate [tex]\sum(x - \bar x) * (y - \bar y)[/tex]
[tex]\sum(x - \bar x) = (15 - 11) * (5 - 8)+ (12 - 11) * (7 - 8) + (10 - 11) * (9 - 8)+ (7 - 11) * (11 - 8)[/tex]
[tex]\sum(x - \bar x) = -26[/tex]
Calculate [tex]\sum(x - \bar x)^2[/tex]
[tex]\sum(x - \bar x)^2 = (15 - 11)^2 + (12 - 11)^2 + (10 - 11)^2 + (7 - 11)^2[/tex]
[tex]\sum(x - \bar x)^2 = 34[/tex]
So:
[tex]b = \frac{\sum(x - \bar x) * (y - \bar y)}{\sum(x - \bar x)^2}[/tex]
[tex]b = \frac{-26}{34}[/tex]
[tex]b_0 = y - bx[/tex]
[tex]b_0 = 5 - \frac{-26}{34}*15[/tex]
[tex]b_0 = 5 + \frac{26*15}{34}[/tex]
[tex]b_0 = 5 + \frac{390}{34}[/tex]
Take LCM
[tex]b_0 = \frac{34*5+ 390}{34}[/tex]
[tex]b_0 = \frac{560}{34}[/tex]
[tex]b_0 = 16.471[/tex]
Can someone just check my answers please? Please let me know which questions are wrong. Thank you for your time.
I need help solving this problem. Thanks
9514 1404 393
Answer:
y = -4/7x +58/7
Step-by-step explanation:
The slope of the given line segment is ...
m = (y2 -y1)/(x2 -x1)
m = (17 -3)/(1 -(-7)) = 14/8 = 7/4
Then the slope of the perpendicular line is ...
-1/m = -4/7 . . . . . slope of the perpendicular bisector.
__
The midpoint of the given line segment is ...
M = 1/2(x1 +x2, y1 +y2)
M = (1/2)(-7 +1, 3 +17) = 1/2(-6, 20) = (-3, 10)
__
The y-intercept of the bisector can be found from ...
b = y -mx
b = 10 -(-4/7)(-3) = 10 -12/7 = 58/7
Then the slope-intercept form equation for the perpendicular bisector is ...
y = mx +b
y = -4/7x +58/7
Which one is a better deal?
a 3 pack of notebooks for $4.50
Or a 12 pack of notebooks for $15.00
A raffle has a grand prize of a European cruise valued at $10000 with a second prize of a Rocky Point vacation valued at $700. If each ticket costs $4 and 11000 tickets are sold, what are the expected winnings for a ticket buyer?
Answer:
- 3.027
Step-by-step explanation:
First price = 10000 ; second price = 700
Number of tickets sold = 11000
Ticket cost = $4
Probability that a ticket wins grand price = 1 / 11000
Probability that a ticket wins second price = 1 / 11000
X ____ 10000 _____ 700
P(x) ___ 1 / 11000 ___ 1/11000
Expected winning for a ticket buyer :
E(X) = Σx*p(x)
E(X) = (1/11000 * 10000) + (1/11000 * 700) - ticket cost
E(X) = 0.9090909 + 0.0636363 - 4
E(X) = - 3.0272728
E(X) = - 3.027
a linear model is appropriate for the data in which scatterplot.?
Answer: (b) or 2
Step-by-step explanation: its the only one linear to the best possibility.
Plzzzz Help
The cost (in dollars) of buying x pounds of a party product is given by the function
C(x) = 10x + 300.
Suppose, for budgetary reasons; you can't spend more than $2100 on this product. You can spend less, but you have to buy at least 50 pounds.
In this situation, what is the domain of this function?
Answer:
180
Step-by-step explanation:
Given the cost (in dollars) of buying x pounds of a party product is given by the function
C(x) = 10x + 300.
Suppose, for budgetary reasons; you can't spend more than $2100 on this product. You can spend less, but you have to buy at least 50 pounds.
To get the domain of the function, substitute C(x) =2100 and find x
2100 = 10x + 300
10x = 2100 - 300
10x = 1800
x = 1800/10
x = 180
Hence the domain of the function is 180
) dy 2x
------ = ---------------
dx yx2 + y
Step-by-step explanation:
[tex]\dfrac{dy}{dx} = \dfrac{2x}{y(x^2 + 1)}[/tex]
Rearranging the terms, we get
[tex]ydy = \dfrac{2xdx}{x^2 + 1}[/tex]
We then integrate the expression above to get
[tex]\displaystyle \int ydy = \int \dfrac{2xdx}{x^2 + 1}[/tex]
[tex]\displaystyle \frac{1}{2}y^2 = \ln |x^2 +1| + k[/tex]
or
[tex]y = \sqrt{2\ln |x^2 + 1|} + k[/tex]
where I is the constant of integration.
51
What is the inverse of the function f(x) = 2x + 1?
Oh(x) =
1
2x-
o h«x)= kx +
- 3x-2
Oh(x) =
Oh(x) =
Mark this and return
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81
O
10:49 AM
^ D 0x
mamman
Answer:
let inverse f(x) be m:
[tex]m = \frac{1}{2x + 1} \\ 2x + 1 = \frac{1}{m} \\ 2x = \frac{1 - m}{m} \\ x = \frac{1 - m}{2m} [/tex]
substitute x in place of m:
[tex]{ \bf{ {f}^{ - 1}(x) = \frac{1 - x}{2x } }}[/tex]
Given the function, calculate the following values...
f(0) = 56
f(2) = 42
f(-2) = 70
f(x+1) = 7|x-7|
f(x²+2) = 7|x²-6|
Answered by GAUTHMATH
The x-value(s) for which f(x)g(x) is/are ___
9514 1404 393
Answer:
x = -1, 1, 9
Step-by-step explanation:
You want x such that f(x) = g(x). Subtracting g(x) from both sides of this equation lets us rewrite it as ...
f(x) -g(x) = 0
x³ -9x² -(x -9) = 0
x²(x -9) -1(x -9) = 0 . . . factor the first pair of terms
(x² -1)(x -9) = 0 . . . . . . use the distributive property
(x -1)(x +1)(x -9) = 0 . . . . factor the difference of squares
Values of x that make these factors zero will make f(x) = g(x):
x = -1, 1, 9 for f(x) = g(x)
it's tooooo easy who wants brain list
Answer:
1) Isosceles
2) Acute
3) Right angled
4( Obtuse
5) Equilateral
Find the surface area and volume of the solid given the figure below
Answer:
Volume - 582.8848178 cm cubed
Step-by-step explanation:
Volume - to fine the volume start with the cone...
The formula is 1/3 pi r^2h
so for this problem it would be
1/3 * 3.14 * 26.01 * 11.2
so your answer would be...
305.061213 cm cubed
Your next step is to find the volume of the dome. to do that the formula is (4/3 pi r^3)/2
so for this problem it would be
(4/3 * 3.14 * 132.651)/2
so your answer would be...
277.8236048 cm cubed
Finally you add together those 2 volumes and get 582.8848178 cm cubed as your final answer.
Question A cotton farmer produced 390 pounds per acre after 4 years of operating. After 9 years, he was producing 460 pounds per acre. Assuming that the production amount has been increasing linearly, estimate the production per acre 7 years after he started farming. Your answer should just be a numerical value. Do not include units in your answer. Provide your answer below:
The house-numbers on a certain street go from 1 to 88. The function B(n) models the type of the building whose number is n according to the following key:
(GRAPH ATTATCHED)
What number type is more appropriate for the domain of B?
A. Integer
B. Real Number
What's the appropriate domain?
Hello,
Answer A
[tex]dom (B(n)) =\{0,1,2,3\} =\{ z\ in \ \mathbb{Z} \ |\ 0 \leq z \leq 4\}[/tex]
Determine whether the point is on the graph of the equation 2x+7y=13
(-4,3)
Is (-4,3) on the graph of 2x+7y=13?
Yes or no?
Answer:
(I) yessssssssssssssssssssssss
Answer:
yes it is.
Step-by-step explanation:
i did this and it was correct
Multiply the polynomials 3(x+7) (show work pls)
Answer:
3x + 21
Step-by-step explanation:
(3)(x+7)
Now, we distribute the 3 in each term of (x+7)
So, 3*x = 3x and 3*7 = 21.
So our resulting term would be 3x+21.
If an odd number is less than 15, then it is prime
Answer:
False
Step-by-step explanation:
To show that this is false, all we have to do is find one example.
9 is an odd number less than 15
9 is composite
9 =3*3
PLSHELPASAPDFFFFFFFFFFFFFFFFFFFFFFFFFF
im struggling with the same one
84 percent of students athletes attend a preseason meeting. If there are 175 students athletes how many attend the meeting
Answer:
Total no. of students =175
percent of students athletes who attend a preseason meeting =84
No. of students who attend the meeting
= 84% of 175
=147
=
The solution set is
1/2(10x+16)-13=-3/5(15x-35)
Answer: 13/7 or as a decimal 1.857142857
How did i get the answer:
Step 1: Simplify both sides of the equation.
so 1/2 of 10 is 5, 1/2 of 16 is 8
-3/5 of 15 is -9 and -3/5 of -35 is POSITIVE 21
all together should look like 5x+8+−13=−9x+21
(now we have to combine like terms)
8+ -13= -5
5x -5 = -9x+21
Step 2: Add 9x to both sides
5x + 9x= 14x
14x -5 = 21
Step 3: Add 5 to both sides.
21+5= 26
14x=26
Step 4: Divide both sides by 14.
26/14= 1.85714286 or 13/7
Need helppppppp please
Answer:
What do you need help with
Step-by-step explanation:
A circle has a circumference of 2cm. Which statement about the circumference and area is true?
A comparison of the area and circumference is not possible since the area cannot be determinec
The numerical values of the circumference and area of the circle are equal.
The numerical value of the circumference is greater than the numerical value of the area.
The numerical value of the circumference is less than the numerical value of the area.
ОО
Answer:
The numerical values of the circumference and area of the circle are equal.
A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 3% margin of error at a 99% confidence level, what size of sample is needed
Answer:
1849
Step-by-step explanation:
Margin of error, E=0.03
Confidence level=0.99
z=2.58
No prior estimate of p is given, so consider p=0.5
Sample size required ,n=2.58^2*0.5*(1-0.5)/0.03^2
n=1849
Determine whether the following propositions are true or false:
(a) 5 is an odd number and 3 is a negative number.
(b) 5 is an odd number or 3 is a negative number.
(c) 8 is an odd number or 4 is not an odd number.
(d) 6 is an even number and 7 is odd or negative.
(e) It is not true that either 7 is an odd number or 8 is an even number (or both).
Answer:
a) false
b) true
c) true
d) true
e) false
Step-by-step explanation:
In a statement of the type:
p ∧ q
where ∧ means "and"
The statement is true only if both p and q are true
the statement is false if p, q, or both, are false.
and in the case of:
p ∨ q
where ∨ means "or"
The statement is true if at least one of p or q (or both) are true.
The statement is false if both are false.
Now that we know that, let's solve the problem:
a) "5 is an odd number and 3 is a negative number."
Here we have:
p = 5 is an odd number
We know that this is true
q = 3 is a negative number
This is false.
then the complete statement is false.
b) "5 is an odd number or 3 is a negative number."
here we have:
p = 5 is an odd number.
this is true
q = 3 is a negative number
because in this case we have an "or", with only p being true, the whole statement is true.
c) "8 is an odd number or 4 is not an odd number."
p = 8 is an odd number (this is false)
q = 4 is not an odd number (this is true, 4 is a even number)
Again, we have an "or", so we need only one true proposition, then the statement is true.
d) "6 is an even number and 7 is odd or negative."
p = 6 is an even number (true)
q = 7 is odd or negative (notice that we have an or, and 7 is odd is true, so this proposition is true)
Then both propositions are true, then the statement is true.
e) "It is not true that either 7 is an odd number or 8 is an even number (or both)."
This is most complex, this will be true if at least one of the propositions is false.
but:
7 is an odd number is true
8 is an even number is true.
Then both statements are true, which means that the statement is false.
jenna is playing an online trivia game. she has 50 points and earns 2 points for each correct answer. she will advance to the next amount if her score is over 68 points. which inequality can jenna use to find how many more questions she must answer correctly to advance to the next round?
Answer:2x + 50 > 68
Step-by-step explanation:
Answer:
7
Step-by-step explanation:
because is you skip count on two you will count on to 68 so that is why the answer is 7.
HELP
BELP
Identify the range of the function shown in the graph
Answer:
Range = -1 ≤ y ≤ 2
Step-by-step explanation:
The function's range is the y-values the function can have as its output. -1 is the minimum y-value and 2 is the maximum y-value.
9.
Find the area of the shaded region.
6
6
The exact area is A =
square units.
Answer:
8. 36
Step-by-step explanation:
8.
The diameter of the square is x=[tex]\sqrt{6^{2} +6^{2} }\\[/tex] = [tex]\sqrt{72}[/tex] = 6 [tex]\sqrt{2}[/tex]
The diameter of the square is the diameter of the circle, therefore the radius of the circle is r = 6 [tex]\sqrt{2}[/tex]/2 = 3[tex]\sqrt{2}[/tex]
The area of the shaded region, which is a circle is A= π[tex]r^{2}[/tex] = π[tex](3\sqrt{2} )^{2}[/tex] = 36π