Answer:
Step-by-step explanation:
3(x + 1 ) =2x - 5 This is the way the equation reads. Remove the brackets.
3x + 3 = 2x - 5 Subtract 2x from both sides
-2x -2x
x + 3 = - 5 Subtract 3 from both sides.
-3 -3
x = - 8
from an observer o, the angles of elevation of the bottom and the top of a flagpole are 40° and 45° respectively.find the height of the flagpole?
Answer:
Take a look of the image below, we can think on this problem as a problem of two triangle rectangles.
We can see that both triangles share the adjacent cathetus, then the height of the flagpole is just the difference between the opposite cathetus.
Remember the relation:
Tan(a) = (opposite cathetus)/(adjacent cathetus)
So, if we define H as the height of the cliff
X as the distance between the observer and the cliff
and h as the height of the flagopole
we can write:
tan(40°) = H/X
tan(45°) = (H + h)/X
Notice that we have two equations and 3 variables (we should have the same number of equations than variables) then here is missing information, and we can't get an exact solution for the height of the flagpole.
But we can write it in terms of the height of the cliff H, or in terms of the distance between the observer and the cliff.
We want to find the value of h.
If we take the quotient between both equations, we get:
Tan(45°)/Tan(40°) = (H + h)/H
1.192 = (H + h)/H
1.192*H = H + h
1.192*H - H = h
0.192*H = h
So the height of the flagpole is 0.192 times the height of the cliff.
rotation 180 degrees about the origin.
Answer:
Take the picture you uploaded.
Click the rotate button twice.
Done
math help plz
how to solve literal equations, how to understand and step by step with an example provided please
9514 1404 393
Explanation:
Your question covers a good bit of the material in an algebra course. The short answer is, "the same way you solve a numerical equation." The point of algebra is that literals can stand for numbers, and so be manipulated the same way numbers are.
Expressions are evaluated according to the Order of Operations. For equations involving a single variable, the equation specifies what operations are being performed on that variable. To find the vale of the variable (solve for that literal), you need to "undo" the operations that are performed on it. As with many problems that have layers, you work down through the layers from the outside in. Generally, that means working through the list of operations "backwards," undoing the last one first.
Simple example
y = mx + b . . . . . . solve for x
In this equation, the operations performed on x are ...
multiplication by maddition of b to the productIn accordance with the above, the first thing we do is "undo" the addition of b. (Note that this could be a number or literal--or even a complicated expression--and the process would be exactly the same.) To "undo" addition, we add the opposite.
y -b = mx +b -b ⇒ y -b = mx
Next, we "undo" the multiplication by m. That is, we divide by m, or multiply by the reciprocal of m. Either is the same as the other.
(y -b)(1/m) = (mx)(1/m) ⇒ (y -b)/m = x
Now, we have solved this literal equation for x.
_____
Throughout this process you must adhere strictly to the properties of equality. That is, anything you do to one side of the equation must also be done to the other side.
The reason you study inverses and identity elements is so you understand that addition of an additive inverse produces the additive identity element:
x + (-x) = 0
Similarly, multiplication by the multiplicative inverse (reciprocal) produces the multiplicative identity element.
x · (1/x) = 1
When other operations are involved, such as raising to a power, trig functions, roots, logs, exponentiation, each of these has an associated inverse function that produces an identity:
(x^a)^(1/a) = x^1 = x
arcsin(sin(x)) = x
(√x)^2 = x
10^(log(x)) = x or log(10^x) = x
Some of these inverse functions have restricted domains, so care must be used when solving equations involving them.
When a variable of interest appears on both sides of the equal sign, then you must figure a way to rearrange the equation so the terms with the variable can be combined.
Example:
ax + b = cx +d . . . . . solve for x
ax -cx = d -b . . . . . . subtract (cx+b). (Of course, this is subtracted from both sides of the equation.)
x(a -c) = d -b . . . . . combine x-terms
x = (d -b)/(a -c) . . . . divide by the coefficient of x
Note that we had to divide the entire right-side expression by the x-coefficient, so had to enclose it in parentheses.
More Complicated Example:
A recent Brainly problem asked for the solution to ...
T = 2π√(L/g) . . . . solve for L
Here, L is divided by g, a root taken, and that multiplied by 2π. Undoing these in reverse order, we first divide by 2π, square both sides to undo the root, then multiply by g to undo the division:
[tex]T=2\pi\sqrt{\dfrac{L}{g}}\\\\\dfrac{T}{2\pi}=\sqrt{\dfrac{L}{g}}\\\\\left(\dfrac{T}{2\pi}\right)^2=\dfrac{L}{g}\\\\\boxed{L=g\left(\dfrac{T}{2\pi}\right)^2}[/tex]
The problem posted on Brainly had numbers where some of these variables are. That does not affect the solution method, except that sometimes numerical values can be combined where literal values cannot.
_____
Key Points
The equal sign is sacred, and its truth must be preserved at every step.Literal equations are solved the same way numerical equations are solved.Inverse operations and functions are used to "undo" operations and functions.The Order of Operations can be helpful when considering what to do first.30 POINTS
Help on Part B pleaseeee
In verse of B.g(x)=[tex]\frac{x+5}{4}[/tex] is:
4x-5
Answer:
Solution given:
B.g(x)=[tex]\frac{x+5}{4}[/tex]
let
g(x)=y
y=[tex]\frac{x+5}{4}[/tex]
Interchanging role of x and y
we get:
x=[tex]\frac{y+5}{4}[/tex]
doing crisscrossed multiplication
4x=y+5
y=4x-5
So
g-¹(x)=4x-5
Given that,
→ g(x) = x+5/4
Then g(x)=y,
→ y = x+5/4
Now we can interchange role of x and y,
→ x = y+5/4
Then use the cross multiplication,
→ 4x = y+5
→ y = 4x-5
Hence, g-¹(x) = 4x-5 is the solution.
would someone help me out with this question? I got it wrong the first time but I don't understand how.
Answers:
Choice 2) Angle ABC is bisected by ray BD.
Choice 3) BC = 1/2 AC
Choice 5) 2*(angle DBC) = angle ABC
================================================
Explanation:
Since B is the midpoint of AC, this means that AC is cut in half to form the smaller equal pieces AB and BC
We can then say
AB+BC = AC
BC+BC = AC
2BC = AC
BC = (1/2)*AC
which shows why choice 3 is one of the answers
----------------------
Angle ABD is shown to be 90 degrees. Let's say we didn't know angle DBC is also 90. Lets call it x
(angle ABD) + (angle DBC) = 180
90 + x = 180
x = 180 - 90
x = 90
So angle DBC is also 90.
We can see that the 180 degree angle (ABC) is cut in half into two smaller 90 degree angles (ABD and DBC). Therefore, angle ABC has been cut in half and that's why choice 2 is another answer.
------------------------
Using the angle addition postulate, we know that,
(angle ABD) + (angle DBC) = angle ABC
(angle DBC) + (angle DBC) = angle ABC
2*(angle DBC) = angle ABC
Showing why choice 5 is the third answer.
------------------------
Choice 1 isn't true since ray BD helps form angle DBC.
Choice 4 isn't true because there isn't a tickmark on segment BD to indicate it's the same length as BC.
(-3,-7) is it a solution
Answer:
It could be a solution
Step-by-step explanation:
This depends on what equation you are solving. It could be a solution for a quadratic or even a transformation problem.
HELP PLEASE!!!!!!!!!!
Answer:
12
Step-by-step explanation:
A humanities professor assigns letter grades on a test according to the following scheme. A: Top 13% of scores B: Scores below the top 13% and above the bottom 60% C: Scores below the top 40% and above the bottom 23% D: Scores below the top 77% and above the bottom 8% F: Bottom 8% of scores Scores on the test are normally distributed with a mean of 70 and a standard deviation of 9.6. Find the minimum score required for an A grade. Round your answer to the nearest whole number, if necessary
Answer:
81
Step-by-step explanation:
Given data:
mean μ = 70.
standard deviation σ, 9.6.
P(Z < 1.123) = 0.13
z = 1.13
Use the z-score formula,
x = z×σ +μ
Substitute the values in the above equation.
x = 1.13 9.6 + 70 = 81
The minimum score required for an A grade is = 81
So for this problem I got the scientific notation however I can not seem to figure out the standard notation. I thought it is the same answer but it is not. Can someone please help me out here please?
Answer:
567000000
Step-by-step explanation:
Standard is the actual number. Multiply 5.67 and 10^8.
y is inversely proportional to x when y=9, x=24
Answer:
216
Step-by-step explanation:
y=k÷x
k=xy
k=9×24
k=216
Mr johnson sells erasers for $3 each. He sold 96 erasers last week and he sold 204 erasers this week.
A. $300 B $600 C $100 D $900
I believe your answer is D.) $900
204 + 96 = 300
300 x 3 = 900
I hope this is correct and helps!
Use quadratic regression to find the
equation for the parabola going
through these 3 points.
(-4, -33) (1, 2) (9, 162)
HELP PLZ
9514 1404 393
Answer:
y = x^2 +10x -9
Step-by-step explanation:
Quadratic regression generally requires the use of "technology" to aid in finding the equation of the curve of best fit. Use the technology you've been introduced to.
__
When only a few data points are provided, I prefer to use the Desmos graphing calculator. It shows the equation to be ...
y = x^2 +10x -9
A researcher conducts a repeated-measures design study comparing 2 treatment conditions and obtains 20 scores in EACH treatment condition. How many participants participated in the study
Answer:
20 participants
Step-by-step explanation:
Given
[tex]Conditions = 2[/tex]
[tex]Scores = 20[/tex]
Type: Repeated design
Required
The number of participants (n)
The repeated measure design implies that the test was conducted repeatedly on the same sample size.
Since the score in each test is 20; then:
[tex]n = 20[/tex] --- the number of participants
What is y=-2(x+3)^2+2
Answer:
y = -2(x + 3)² + 2
y = 2{ -(x + 3)²+ 1}
y = 2{ -(x² + 6x + 9) + 1}
y = 2{ -x² - 6x - 9 + 1}
y = 2{ -x² - 6x - 8 }
y = -2 { x² + 6x + 8}
OR
y = -2{(x + 4)(x + 2)}
Here is the general information about the Learn by Doing discussion board exercises (directions, grading, feedback). Prompt
1) Give an example of a research question that involves estimating a characteristic about the population of part-time students at your college.
2) Improve this poorly stated research question: Do students work a lot of hours
Answer:
Step-by-step explanation:
Answer to question 1:
On average do part-time students spend less than 20 hours per work on academic work and assignments ?
Answer to question 2:
On average do students work greater than 50 hours a week ?
The volume, V, of a sphere in terms of its radius, r, is given by , V(r)=4/3(pie)r^3. Express r as a function of V, and find the radius of a sphere with volume of 150 cubic feet. Round your answer for the radius to two decimal places.
r(V)=
A sphere with volume 150 cubic feet has radius
_________ feet.
Step-by-step explanation:
If
[tex]V=\dfrac{4\pi}{3}r^3[/tex]
then we can solve for r as
[tex]r = \sqrt[3]{\dfrac{3V}{4\pi}}[/tex]
If the volume of the sphere is 150 ft^3, then the radius is
[tex]r = \sqrt[3]{\dfrac{3(150\:\text{ft}^3)}{4\pi}} = 3.30\:\text{ft}[/tex]
The radius of the given sphere with a volume of 150 cubic feet is 2.29 feet, correct to two decimal places.
Given that
the volume of a sphere = 150 cubic feet.
the radius of the sphere=????
what is a Sphere?a round solid figure, or its surface, with every point on its surface equidistant from its center.
as we know,
the volume of a sphere
[tex]V=\frac{4}{3} *\pi *r^3[/tex]
[tex]r = \sqrt[3]{\frac{3V}{4\pi } }[/tex][tex]r = \sqrt[3]{\frac{3*150}{4\pi } }[/tex][tex]=2.29 feet[/tex]
therefore, the radius of the given sphere is 2.29feet
to get more about sphere refer to the link,
https://brainly.com/question/22807400
How would you write 8^5 as a multiplication expression?
Answer:
8 * 8 * 8 * 8 * 8
Step-by-step explanation:
8^5 is basically 8 times itself five times.
the complement of guessing 5 correct answers on a 5 question true or false examination is
Answer:
Guessing at least one incorrect answer
Step-by-step explanation:
The complement of guessing 5 correct answers on a 5-question true/false exam is-
Guessing at least one incorrect answer because, when 1 or more questions are incorrectly guessed, the event of 5 correct answers can not occur.
Simplify the radical expression below square root of 5/64
A square root 5/8
B 5/64
C square root 5/64
D 5/8
Answer:
a
Step-by-step explanation:
square root distribute to numerator and denominator so both get square rooted [tex]\sqrt{5}[/tex]/8
Last year, Manuel deposited $7000 into an account that paid 11% interest per year and $1000 into an account that paid 5% interest per year. No withdrawals were made from the accounts. Answer the questions below. Do not do any rounding. (a) What was the total interest earned at the end of year? (b) What was the percent interest for the total deposited?
Answer:
The total interest earned at the end of the year was $ 820, and the interest generated by the total deposited was 10.25%.
Step-by-step explanation:
Given that last year, Manuel deposited $ 7000 into an account that paid 11% interest per year and $ 1000 into an account that paid 5% interest per year, and no withdrawals were made from the accounts, to determine what was the total interest earned at the end of year and what was the percent interest for the total deposited, the following calculations must be performed:
7000 x 0.11 + 1000 x 0.05 = X
770 + 50 = X
820 = X
8000 = 100
820 = X
820 x 100/8000 = X
82,000 / 8,000 = X
10.25 = X
Therefore, the total interest earned at the end of the year was $ 820, and the interest generated by the total deposited was 10.25%.
Assisted-Living Facility Rent. Costs are rising for all kinds of medical care. The mean monthly rent at assisted-living facilities was reported to have increased 17% over the last five years to $3486. Assume this cost estimate is based on a sample of 120 facilities and, from past studies, it can be assumed that the population standard deviation is .
Complete Question
Assisted-Living Facility Rent.Costs are rising for all kinds of medical care. The mean monthly rent at assisted-living facilities was reported to have increased 17% over the last five years to $3486 (the Wall Street Journal, October 27, 2012). Assume this cost estimate is based on a sample of 120 facilities and, from past studies, it can be assumed that the population standard deviation is s = $650. a. Develop a 90% confidence interval estimate of the population mean monthly rent.
Answer:
[tex]CI: 3388.39<X<3583.61[/tex]
Step-by-step explanation:
Sample Size n=120
Mean \=x =3486
Standard Deviation \sigma=650
Confidence interval CI=0.9
Therefore
Level of sig [tex]\alpha=0.1[/tex]
Therfore
The Critical Value from table is
Z_c=1.645
Generally the equation for Standard error is mathematically given by
[tex]S.E=\frac{\sigma}{\sqrt{n}}[/tex]
[tex]S.E=\frac{650}{\sqrt{120}}[/tex]
[tex]S.E=59.3366[/tex]
Generally the equation for Margin error is mathematically given by
[tex]M.E= = Z_c * SE[/tex]
[tex]M.E=1.65 * 59.34[/tex]
[tex]M.E= 97.61[/tex]
Therefore
[tex]CI= \=x \pm M.E[/tex]
[tex]CI= 3486 \pm 97.61[/tex]
Lower limit
[tex]LL= \=x-M.E=3486-97.6087[/tex]
[tex]LL= 3388.39[/tex]
Upper limit:
[tex]UL= \=x+E=3486+97.6087[/tex]
[tex]UL= 3583.61[/tex]
Therefore The 90% confidence interval estimate of the population mean monthly rent.
[tex]CI: 3388.39<X<3583.61[/tex]
nit 4 Topic 3 HW Sets Applications e Sunday by 11:59pm Points 100 Submitting an external tool Question How many subsets and proper subsets does the set M = {1,2,3} have? Select the correct answer below:
Answer:
ghthtf
Step-by-step explanation:
tygtgg
You buy a six pack of Gatorade for $9.00. What is the unit price or the price per bottle?
Answer:
Price per bottle is 1.5 or $1.50
Step-by-step explanation:
To get price per unit, you just divide the amount of money spent by the items purchased. 9/6 = 1.5
CHECK MY ANSWERS PLEASE
____
The sequence is geometric:
3, 13, 23, 33,...
True
False***
_____________________
The sequence is geometric:
5, -25, 125, -625,...
True***
False
Answer:
1. False 2. True
Step-by-step explanation:
For a geometric sequence,
[tex]\dfrac{a_2}{a_1}=\dfrac{a_3}{a_2}[/tex]
1. The sequence is :
3, 13, 23, 33,...
[tex]\dfrac{13}{3}\ne \dfrac{23}{13}[/tex]
It is not geometric. It is false
2. The sequence is :
5, -25, 125, -625
[tex]\dfrac{-25}{5}=\dfrac{125}{-25}\\\\-5=-5[/tex]
So, the sequence is geometric as the common ratio is same. It is true.
through: (-2, 2), parallel to y=-x-5
Answer:
y = -x.
Step-by-step explanation:
The slope of the line (m) = -1. ( because of the -x in y = -x - 5)
y - y1 = m (x - x1) where (x1, y1) is a point on the line, so we get;
y - 2 = -1(x - (-2))
y - 2 = -x + -1 * +2
y - 2 = -x - 2
y = -x.
A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid. If the dean wanted to estimate the proportion of all students receiving financial aid to within 1% with 90% reliability, how many students would need to be sampled
Answer:
6546 students would need to be sampled.
Step-by-step explanation:
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 z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
The dean randomly selects 200 students and finds that 118 of them are receiving financial aid.
This means that [tex]n = 200, \pi = \frac{118}{200} = 0.59[/tex]
90% confidence level
So [tex]\alpha = 0.1[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].
If the dean wanted to estimate the proportion of all students receiving financial aid to within 1% with 90% reliability, how many students would need to be sampled?
n students would need to be sampled, and n is found when M = 0.01. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.01 = 1.645\sqrt{\frac{0.59*0.41}{n}}[/tex]
[tex]0.01\sqrt{n} = 1.645\sqrt{0.59*0.41}[/tex]
[tex]\sqrt{n} = \frac{1.645\sqrt{0.59*0.41}}{0.01}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.645\sqrt{0.59*0.41}}{0.01})^2[/tex]
[tex]n = 6545.9[/tex]
Rounding up:
6546 students would need to be sampled.
Find all relative extrema of the function. Use the Second Derivative Test where applicable. (If an answer does not exist, enter DNE.)
f(x) = x² + 5x – 2
relative maximum
(x, y) = DNE
relativo minimum
(x, y) =
Answer:
Relative minimum: [tex]\left(-\frac{5}{2}, -\frac{33}{4}\right)[/tex], Relative maximum: [tex]DNE[/tex]
Step-by-step explanation:
First, we obtain the First and Second Derivatives of the polynomic function:
First Derivative
[tex]f'(x) = 2\cdot x + 5[/tex] (1)
Second Derivative
[tex]f''(x) = 2[/tex] (2)
Now, we proceed with the First Derivative Test on (1):
[tex]2\cdot x + 5 = 0[/tex]
[tex]x = -\frac{5}{2}[/tex]
The critical point is [tex]-\frac{5}{2}[/tex].
As the second derivative is a constant function, we know that critical point leads to a minimum by Second Derivative Test, since [tex]f\left(-\frac{5}{2}\right) > 0[/tex].
Lastly, we find the remaining component associated with the critical point by direct evaluation of the function:
[tex]f\left(-\frac{5}{2} \right) = \left(-\frac{5}{2} \right)^{2} + 5\cdot \left(-\frac{5}{2} \right) - 2[/tex]
[tex]f\left(-\frac{5}{2} \right) = -\frac{33}{4}[/tex]
There are relative maxima.
A statistics class weighed 20 bags of grapes purchased from the store. The bags are advertised to contain 16 ounces, on average. The class calculated the 90% confidence interval for the true mean weight of bags of grapes from this store to be (15.875, 16.595) ounces. What is the sample mean weight of grapes, and what is the margin of error?
O The sample mean weight is 15.875 ounces, and the margin of error is 16.595 ounces.
O The sample mean weight is 16.235 ounces, and the margin of error is 0.360 ounces.
O The sample mean weight is 16.235 ounces, and the margin of error is 0.720 ounces.
O The sample mean weight is 16 ounces, and the margin of error is 0.720 ounces.
Answer:
The sample mean weight is 16.235 ounces, and the margin of error is 0.360 ounces
Step-by-step explanation:
To find the sample mean, we can find the mean of the confidence interval.
(15.875 + 16.595)/2 = 16.235
To find the margin of error, that is the difference between the mean and one of the edges of the confidence interval. 16.595 - 16.235 = 0.36
The sample mean weight is 16.235 ounces, and the margin of error is 0.360 ounces
Answer:
C. We are 90% confident that the interval from 15.875 ounces to 16.595 ounces captures the true mean weight of bags of grapes.
Step-by-step explanation:
3. Determine the Area and Perimeter of the
shape below.
13
5
12
Answer:
Perimeter: 30 Area: 30
Step-by-step explanation:
Perimeter of a triangle= Add all sides = 5+12+13 = 30
Area of a triangle= (B*H)/2 = (5*12)/2 = 60/2 = 30
Hope this helps! :)
True or false: If you are changing a larger unit into a smaller unit, like cm into mm, the decimal is moved to the right because you are multiplying by a power of ten
Answer:true
Step-by-step explanation:
i dont know