Answers
Answer:
A
Step-by-step explanation:
Recall that for a quadratic equation of the form:
[tex]0=ax^2+bx+c[/tex]
The number of solutions it has can be determined using its discriminant:
[tex]\Delta = b^2-4ac[/tex]
Where:
If the discriminant is positive, we have two real solutions. If the discriminant is negative, we have no real solutions. And if the discriminant is zero, we have exactly one solution.We have the equation:
[tex]2x^2+5x-k=0[/tex]
Thus, a = 2, b = 5, and c = -k.
In order for the equation to have exactly one distinct solution, the discriminant must equal zero. Hence:
[tex]b^2-4ac=0[/tex]
Substitute:
[tex](5)^2-4(2)(-k)=0[/tex]
Solve for k. Simplify:
[tex]25+8k=0[/tex]
Solve:
[tex]\displaystyle k = -\frac{25}{8}[/tex]
Thus, our answer is indeed A.
Related Questions
A lab technician needs 35 ml of 15% base solution for a certain experiment,
but she has only 10% solution and 20% solution. How many milliliters of
the 10% and the 20% solutions should she mix to get what she needs?
Answers
Answer:
17.5ml- of 10 percent solution, 17.5ml- of 20 percent solution
Step-by-step explanation:
35:100*15=5.25- ml of alkali in the base solution
Suppose we need x ml of 10 percents solution and 35-x - of 20 percents.
Then The quantity of alkali in the first one (10 percents) is x/100*10=0.1x
when in the second one we have (35-x)/100*20= 7-0.2x of alkali
0.1x+7-0.2x=5.25
7-0.1x= 5.25
0.1x=1.75
x=17.5- 0f 10 percents
35-17.5=17.5 - of 20 percents
A company produces 2 types of computers; desktops and laptops
Answers
Answer:
?
Step-by-step explanation:
4. Write 3x(x + 4)(x - 1) in standard form.
3x3 + 9x2 - 12x
3x3
- 12x + 9x2
3x3 + 9x2 - 12x + 1
1 - 12x + 9x2 + 3x3
Answers
Answer:
i thank the ans id 450
Step-by-step explanation:
find the values of x and y for the following matrix equations
Answers
Answer:
Step-by-step explanation:
Determine whether the following individual events are independent or dependent. Then find the probability of the combined event.
Randomly drawing and immediately eating two red pieces of candy in a row from a bag that contains red pieces of candy out of pieces of candy total.
Answers
Answer:
Dependent event
[tex]P(Red = 2) = \frac{5}{588}[/tex]
Step-by-step explanation:
Given
[tex]Total = 49[/tex]
[tex]Red = 5[/tex]
Solving (a): Are the events dependent?
Yes, they are.
When the first red candy is selected and eaten, the total number of candies reduced to 48 and the number of red candies also reduced to 4.
So, the probability of selecting a 2nd candy is dependent on the first candy selected.
Solving (b): P(Red = 2)
This is calculated as:
[tex]P(Red = 2) = P(Red) * P(Red | Red)[/tex]
The first selection has the following probability:
[tex]P(Red) = \frac{Red}{Total}[/tex]
[tex]P(Red) = \frac{5}{49}[/tex]
The second selection has the following probability:
[tex]P(Red|Red) = \frac{Red - 1}{Total - 1}[/tex]
[tex]P(Red|Red) = \frac{5 - 1}{49 - 1}[/tex]
[tex]P(Red|Red) = \frac{4}{48}[/tex]
So, we have:
[tex]P(Red = 2) = P(Red) * P(Red | Red)[/tex]
[tex]P(Red = 2) = \frac{5}{49} * \frac{4}{48}[/tex]
Reduce fraction
[tex]P(Red = 2) = \frac{5}{49} * \frac{1}{12}[/tex]
Multiply
[tex]P(Red = 2) = \frac{5}{588}[/tex]
helppp outt plss....
Answers
============================================================
Explanation:
For any cyclic quadrilateral (aka inscribed quadrilateral), the opposite angles are always supplementary.
One pair of such angles is A and C
A+C = 180
x+y = 180 is one equation to form
The other pair of supplementary angles is B and D
B+D = 180
y-45+2x+15 = 180
2x+y-30 = 180
2x+y = 180+30
2x+y = 210 is the other equation to form
--------------
So the system of equations we have is
[tex]\begin{cases}x+y = 180\\2x+y = 210\end{cases}[/tex]
Both equations involve 'y', with the same coefficient, so we can subtract straight down to eliminate this variable.
The x terms subtract to x-2x = -xThe y terms subtract to y-y = 0y = 0, so the y terms go awayThe right hand sides subtract to 180-210 = -30We end up with -x = -30 which solves to x = 30
--------------
Once we know x, we can determine y by plugging it into any equation involving x,y and solving for y
Let's say we picked on the first equation
x+y = 180
30+y = 180
y = 180-30
y = 150
Or we could pick on the second equation
2x+y = 210
2(30) + y = 210
60+y = 210
y = 210-60
y = 150
Only one equation is needed. However, doing both like this shows that we get the same y value, and it helps confirm the answers.
In a scatter plot, each ____. Group of answer choices individual is represented by a single point group mean is represented by a single point individual is represented by two data points group mean is represented by two data points
Answers
Answer:
Individual is represented by a single point
Step-by-step explanation:
work out the value of y when x = 4 30 points
Answers
Answer:
y = 54/25 when x = 4.
Step-by-step explanation:
y is given by the equation:
[tex]\displaystyle y = p\times q^{x-1}[/tex]
Where p and q are numbers.
We are also given that when x = 1, y = 10 and when x = 6, y = 0.7776.
And we want to determine the value of y when x = 4.
Since y = 10 when x = 1:
[tex]\displaystyle (10) = p\times q^{(1)-1}[/tex]
Simplify:
[tex]10 = p \times q^0[/tex]
Any number (except for zero) to the zeroth power is one. Hence:
[tex]p=10[/tex]
Thus, our equation is now:
[tex]y = 10\times q^{x-1}[/tex]
When x = 6, y = 0.7776. Thus:
[tex](0.7776) = 10\times q^{(6)-1}[/tex]
Simplify and divide both sides by ten:
[tex]\displaystyle 0.07776 = q^5[/tex]
Take the fifth root of both sides:
[tex]\displaystyle q = \sqrt[5]{0.07776}[/tex]
Use a calculator. Hence:
[tex]\displaystyle q = \frac{3}{5} = 0.6[/tex]
Our completed equation is:
[tex]\displaystyle y = 10\times \left(\frac{3}{5}\right)^{x-1}[/tex]
Then when x = 4, y equals:
[tex]\displaystyle \begin{aligned} y &= 10\times \left(\frac{3}{5}\right)^{(4)-1} \\ \\ &= 10\times \left(\frac{3}{5}\right)^3 \\ \\ &= 10\times \left(\frac{27}{125}\right) \\ \\ &= \frac{54}{25}\end{aligned}[/tex]
The length AB of a rectangle ABCD is 8cm and its diagonal BD and measures 10 cm Find its breadth BC
Answers
what vulnerable does the 4 represents in the number 487.009
Answers
Answer:
400 :D
Step-by-step explanation:
(WILL GIVE YOU 30 POINTS!!!)
The graph shows the functions f(x), p(x), and g(x):
Graph of function g of x is y is equal to 3 multiplied by 1.2 to the power of x. The straight line f of x joins ordered pairs minus 3, minus 3 and 4, 4 and is extended on both sides. The straight line p of x joins the ordered pairs minus 6, 1 and minus 3, minus 3 and is extended on both sides.
Part A: What is the solution to the pair of equations represented by p(x) and f(x)? (3 points)
Part B: Write any two solutions for f(x). (3 points)
Part C: What is the solution to the equation p(x) = g(x)? Justify your answer. (4 points)
Answers
Answer:
(a) No solution
(b)
[tex](x_1,y_1) =(-3,-3)\\(x_2,y_2) =(4,4)[/tex]
(c) [tex](-6,1)[/tex]
Step-by-step explanation:
Given
See attachment for graph
Solving (a): Solution to p(x) and f(x)
Curve p(x) and line f(x) do not intersect.
So, there is no solution to the pair of p(x) and f(x)
Solving (b): Two solutions to f(x)
This means that we select any two point on straight line f(x)
From the line of f(x), we have:
[tex](x_1,y_1) =(-3,-3)\\(x_2,y_2) =(4,4)[/tex]
Solving (c): Solution to p(x) = g(x)
Here, we write out the point of intersection of p(x) and g(x)
From the graph, the point of intersection is: [tex](-6,1)[/tex]
Which best describes the process of selecting a cluster sample?
Clusters that each represent the population are sampled from such that no two members of the same cluster are included in the sample.
Members of a population are organized in clusters, each of which is representative of the population, and then whole clusters are randomly selected to make up the sample.
Members of a population are ordered by some characteristic, and then a cluster sample is formed by selecting every kth member.
Members of a population are separated into clusters based on a characteristic important to the study and a random sample is selected from each cluster.
Answers
Answer:
"Members of a population are organized in clusters, each of which is representative of the population, and then whole clusters are randomly selected to make up the sample"
Step-by-step explanation:
In cluster random sampling, "the population is divided, usually geographically, into groups that generally have the same size. A certain number of groups are randomly chosen, and every individual in the chosen groups are chosen for the sample."
In accord with this logic, the second choice, "Members of a population are organized in clusters, each of which is representative of the population, and then whole clusters are randomly selected to make up the sample" seems to be correct.
NOTE: This may not be the correct answer. I am simply basing my answer on the definition I have learnt.
Answer:
B
Step-by-step explanation:
Solve for x . 7 - (2 x + 11) + 3(3 - x ) = 20
A.7/5
B.-3
C.-4
Answers
Answer:
the answer to the question is a:-3
Solve for x
X-8 = -10
A) X = 2
B) X = -2
C) X = 18
D) X = -18
Answers
Answer:
x=–2
Step-by-step explanation:
x-8=-10
x=-10-8
x=–2
Answer:
-8= -10
, = -10+8
, = -2
The following section is a statement from the rental agreement Tim signed when he rented his car this past weekend. “Upon checkout, the fuel level of the vehicle will be determined by turning the vehicle on and visually inspecting the fuel gauge. The approximate fuel level will be recorded on the Check-Out sheet and verified with initials by the vehicle Renter. One copy of the Check-Out sheet will be given to the customer. Another copy will be kept with the on-site records of the vehicle. The rented vehicle must be returned with a minimum fuel level the same as that indicated on the Check-Out sheet. A vehicle returned with a fuel level less than the approximate level indicated on the Check-Out sheet will be completely refueled with on-site pumps. The price of the fuel used to refuel the vehicle will be added to the Renter’s total charge at a cost of $4.50 per gallon plus a $5.00 re-fueling charge.” As a part of the check-out process, it is customary for a car rental agency to look over the car with the customer and fill out the Check-Out sheet together. As Tim was walking around the car looking for damages that he didn’t want to be held responsible for, the agency representative turned on the car, took note of the fuel level, and indicated it on the Check-Out sheet. Since Tim didn’t have any questions, the clerk handed him the keys and a copy of the Check-Out sheet and wished him well. Which action invalidates the contract Tim signed with the rental agency? a. Tim failed to notice a dent under the right front fender. b. The representative failed to give Tim a copy of the Check-Out sheet. c. The representative failed to have Tim initial by the fuel level on the Check-Out sheet. d. Neither Tim nor the representative checked the oil level in the car.
Answers
Answer:
C. The representative failed to have Tim initial by the fuel level on the Check-Out sheet.
Step-by-step explanation:
After reading the paragraph, we can eliminate B, by seeing that the representative did give him a copy of the Check-Out sheet, as quoted. "Since Tim didn’t have any questions, the clerk handed him the keys and a copy of the Check-Out sheet and wished him well.".
We can also eliminate A and D, as the contract stated nothing about dents or the oil level in the car.
The answer is C, as the representative failed to have Tim initial on the Check-Out sheet. That is a requirement for the contract to be valid, as stated. "The approximate fuel level will be recorded on the Check-Out sheet and verified with initials by the vehicle Renter.". However, Tim never initialed by the fuel level, as stated here. "...the agency representative turned on the car, took note of the fuel level, and indicated it on the Check-Out sheet. Since Tim didn’t have any questions, the clerk handed him the keys and a copy of the Check-Out sheet and wished him well.". No where here does it state that Tim initialed on the Check-Out sheet, meaning that he didn't. Him not doing so invalidates the contract.
A math class has a total of 31 students. The number of females is seven less than the number of meals. How many miles and how many females are in the class?
Answers
Answer:
Male-19&Female-13
Step-by-step explanation:
See the image for solution
Hope it helps
Have a great day
The critical value of F for an upper tail test at a 0.05 significance level when there is a sample size of 21 for the sample with the smaller variance and there is a sample size of 9 for the sample with the larger sample variance is _____. a. 2.94 b. 2.45 c. 2.10 d. 2.37
Answers
Answer:
2.45
Step-by-step explanation:
Given that :
α = 0.05
Larger sample variance= numerator, sample size = 9
Smaller sample variance = denominator, sample size = 21
Hence,
DFnumerator = n - 1 = 9 - 1 = 8
DFdenominator = n - 1 = 21 - 1 = 20
Critical value for upper tail test using the F distribution table at α = 0.05 ; DFnumerator on horizontal ; Df denominator as vertical ;
F critical = 2.447
F critical = 2.45
What is the five-number summary for this data set? 22, 29, 33, 38, 44, 47, 51, 56, 64, 69 Assume the numbers in each answer choice are listed in this order: min, Q1, median, Q3, max.
A. 22, 33, 45.5, 56, 69
B. 22, 38, 45.5, 51, 69
C. 22, 38, 41, 51, 69
D. 22, 33, 41, 56, 69
Answers
Answer: A: 22, 33, 45.5, 56, 59
Step-by-step explanation:
The minimum is the lowest number in the data, in this case, it was 22.
Q1 is the median of the lower quartile range, anything below the median of the overall data.
Median, the middle number in the overall data. You first need to put them from lowest to highest (numerical order). After that, I find it a lot easier to cross one from each side until I'm either left with one or two. If I'm left with one, then that is my median for the overall data set. If I'm left with two, then I simply need to add both the numbers together and divide it by 2. Typically if it is a whole number, and the numbers are 1 number value away from each other, it is usually just 0.5 more of the lower value of the two. (For example, the two numbers I come down to is 10 and 11. The median would be 10.5).
Q3 is the exact same principle as Q1 just on the upper quartile range. Just repeat what you did in Q1 but for the numbers above the overall median of the data set.
Maximum is the highest number in the data set, in this case, it was 69.
Hope this helps!
Tìm vi phân toàn phần của các hàm số sau:
ln(x+√(x^2+y^2 ) ) ln(sin(y/x))
Answers
Let f = ln(x + √(x ² + y ²)) ln(sin(y/x)).
Then the total differential is
[tex]\mathrm df = \dfrac{\mathrm d\left(x+\sqrt{x^2+y^2}\right)}{x+\sqrt{x^2+y^2}}\ln\left(\sin\left(\dfrac yx\right)\right) + \ln\left(x+\sqrt{x^2+y^2}\right)\dfrac{\mathrm d\left(\sin\left(\frac yx\right)\right)}{\sin\left(\frac yx\right)}[/tex]
[tex]\mathrm df = \dfrac{\mathrm dx + \frac{\mathrm d(x^2+y^2)}{\sqrt{x^2+y^2}}}{x+\sqrt{x^2+y^2}}\ln\left(\sin\left(\dfrac yx\right)\right) + \ln\left(x+\sqrt{x^2+y^2}\right)\dfrac{\cos\left(\frac yx\right)\,\mathrm d\left(\frac yx\right)}{\sin\left(\frac yx\right)}[/tex]
[tex]\mathrm df = \dfrac{\mathrm dx + \frac{2x\,\mathrm dx+2y\,\mathrm dy}{\sqrt{x^2+y^2}}}{x+\sqrt{x^2+y^2}\right)\ln\left(\sin\left(\dfrac yx\right)\right) + \ln\left(x+\sqrt{x^2+y^2}}\right)\dfrac{\cos\left(\frac yx\right)\frac{x\,\mathrm dy-y\,\mathrm dx}{x^2}}{\sin\left(\frac yx\right)}[/tex]
[tex]\mathrm df = \dfrac{\left(2x+\sqrt{x^2+y^2}\right)\,\mathrm dx +2y\,\mathrm dy}{x\sqrt{x^2+y^2}+x^2+y^2\right)\ln\left(\sin\left(\dfrac yx\right)\right) \\\\ \indent + \dfrac1{x^2}\cot\left(\dfrac yx\right)\ln\left(x+\sqrt{x^2+y^2}}\right)(x\,\mathrm dy-y\,\mathrm dx)[/tex]
[tex]\mathrm df = \left(\left(\dfrac{2x+\sqrt{x^2+y^2}}{x\sqrt{x^2+y^2}+x^2+y^2}\right)\ln\left(\sin\left(\dfrac yx\right)\right) - \dfrac y{x^2}\cot\left(\dfrac yx\right)\ln\left(x+\sqrt{x^2+y^2}\right)\right)\,\mathrm dx \\\\ \indent + \left(\dfrac{2y}{x\sqrt{x^2+y^2}+x^2+y^2}\ln\left(\sin\left(\dfrac yx\right)\right)+\dfrac1x\cot\left(\dfrac yx\right)\ln\left(x+\sqrt{x^2+y^2}\right)\right)\,\mathrm dy[/tex]
Sets L and M are defined as follows.
L={-1,1,4,5,7,8)
M={1,2,7)
Answer each part below. Write your answer in roster form or as Ø.
(a) Find the union of L and M.
(b) Find the intersection of L and M
Answers
Answer:
the union of l and m is minus 1,1,2,4,5,7,8.....and the intersection of l and m is 1.......
find the value of z, angles related to a circle
Answers
Explanation:
z + 70 = 180 (supplementary angle)
z = 180 - 70
z = 110
Find the length of DM
Answers
Answer:
67
Step-by-step explanation:
DM=JM-JD=84-17=67
Answer:
Step-by-step explanation:
Find the missing side round your answer to the nearest tenth
Answers
Answer: 15
Step-by-step explanation:
Near the beginning of Lesson 5.3, a strategy for factoring trinomials of the form x^2+ bx+c was
developed by exploring the product of the binomials (x+p) and (x+q).
Explain how the development of this factoring strategy is an example of working backwards
to solve a problem.
Answers
Answer:
Step-by-step explanation:
there are function that "invert" each other..
subtraction inverts addition...
3+2 = 5 ... 5-2 = 3
division inverts multiplication
5*2 = 10 ... 10/2 = 5
Using that concept, "factoring" is basically the inverse of multiplication
3x^2 + 9x can be factored to 3x(x+3)
if you multiply that out it reverts back to the original equation
so x^2 + 5x + 6 factors to (x+3)(x+2)
if you multiply that out (foil it)
you get x^2 + 5x + 6
Find the area bounded by the curves x = 2y2 and x = 1 - y. Your work must include an integral in one variable.
Please help!!
Answers
Answer:
Hello,
in order to simplify, i have taken the inverses functions
Step-by-step explanation:
[tex]\int\limits^\frac{1}{2} _{-1} {(-2x^2-x+1)} \, dx \\\\=[\frac{-2x^3}{3} -\frac{x^2}{2} +x]^\frac{1}{2} _{-1}\\\\\\=\dfrac{-2-3+12}{24} -\dfrac{-5}{6} \\\\\boxed{=\dfrac{9}{8} =1.25}\\[/tex]
Country Financial, a financial services company, uses surveys of adults age 18 and older to determine whether personal financial fitness is changing over time. A recent sample of 1000 adults showed 410 indicating that their financial security was more than fair. Just a year prior, a sample of 900 adults showed 315 indicating that their financial security was more than fair. Conduct the hypothesis test and compute the p-value. Round your answer to four decimal places. What is the 95% confidence interval estimate of the difference between the two population proportions? Round your answers to four decimal places.
Answers
Answer:
hey, how you're day going
Step-by-step explanation:
.................
What is 3 times 10^9
Answers
Answer:
3 times 10 ^ 9
Step-by-step explanation:
3 × 10 ^ 9 = 3000000000
What is the GCF of the expression 7xyz - 21xyz + 49yz + 14yz2?
Answers
Answer:
7yz
Step-by-step explanation:
You can take 7yz common from all the terms in the given expression
Answered by GAUTHMATH
If £15=$20 and $5=390 find the number of pounds that can be exchanged
200
Answers
Mark as braianlist
15 multiple by 5 equal 75 -390 equal 315 -15equal 200
Convert 2 1/3 into improper fraction: *
7/3
O 7/6
O 6/3
O 3/6
Answers
Answer:
7/3 is the answer
Step-by-step explanation:
