Answer:
a=5, a=-2.5
Step-by-step explanation:
Given:
[tex]2 a^2 - 5 a - 25 = 0[/tex]
Solution:
[tex]a_{1,\:2}=\frac{-\left(-5\right)\pm \sqrt{\left(-5\right)^2-4\cdot \:2\left(-25\right)}}{2\cdot \:2}[/tex]
[tex]a_{1,\:2}=\frac{-\left(-5\right)\pm \:15}{2\cdot \:2}[/tex]
[tex]a_1=\frac{-\left(-5\right)+15}{2\cdot \:2},\:a_2=\frac{-\left(-5\right)-15}{2\cdot \:2}[/tex]
[tex]a=5,\:a=-2.5[/tex]
~Lenvy~
what is the formula for the volume of a sphere with radius r = 5?
Answer:
V = (4/3)π·5³ = 500π/3
Step-by-step explanation:
The formula for the volume of any sphere as a function of its radius is ...
V = (4/3)π·r³
When the sphere has a radius of 5, we replace r in the formula with 5. The formula for the volume of a sphere with radius 5 is ...
V = (4/3)π·5³
__
When that is evaluated, the volume is found to be ...
V = 500π/3 ≈ 523.599 . . . cubic units
A researcher is interested in determining whether teens who transfer schools after their freshman year in high school demonstrate
more behavior problems on the Achenbach Youth Self Report test with a population mean of 50 and a population standard deviation of
10. The researcher has a sample of 100 teens with a mean score of 59. What is your obtained z?
The z-score of the number of teens that transfered schools is the standard score
The obtained value of z is 5
How to determine the value of z?The given parameters are:
Population mean, μ = 50Population standard deviation, σ = 10Sample, x = 100Sample mean = 59The z-value is calculated using:
z = (x - μ)/σ
Substitute known values in the above formula
z = (100 - 50)/10
Evaluate the difference
z = 50/10
Evaluate the quotient
z = 5
Hence, the obtained value of z is 5
Read more about z-scores at:
https://brainly.com/question/25638875
What are levels of mathematical acquisition in pre-junior
Answer: Number Sense – Understanding Quantity.
Representation – Using Symbols and Words to Represent Numbers.
Shapes and Spatial Relationships (Geometry)
Measurement – Comparing and Communicating about size.
Patterns – Recognizing and Making Patterns.
Problem Solving.
Step-by-step explanation: boom!
The figure is made up of a cylinder and a half sphere. What is the volume of the composite figure? Use 3.14 for Pi. Round to the nearest hundredth.
A cylinder and half sphere. Both have a radius of 4 millimeters. The cylinder has a height of 7 millimeters.
Recall the formulas V = B h and V = four-thirds pi r cubed
Answer:
351.68 millimeters for the cylinder and 8 23/75 millimeters for the half circle.
Step-by-step explanation:
Volume Cylinder = 3.14(16)(7) = 351.68
Volume Half sphere = 2/3(3.14)(4) = 8 23/75
If you want both of them together just add up the two numbers.
Answer:
351.68 millimeters cylinder
8 23/75 millimeters half circle
Step-by-step explanation:
Beth Hazelton purchased a compact vehicle with an $18,240.00. MSRP including the delivery and title fee. She selected a leather interior which costs 5 times the upgraded stereo system. If the total cost of the vehicle, including a 7% sales tax, was $21,365.20 find the cost of the (a) stereo system and (b) leather interior. Use the example in the book to help you with solving this problem.
Answer:
price of leather thingy= $2906.62
price of stereo system = $581.33
Step-by-step explanation:
final cost minus cost of total before adding the leather.
21,365.20
- 18,240.00
= $3125.2
to find the exact price of the leather since the 7% tax was included in the price we mulitply by .93
3125.2 x .93 = 2906.62
we know the stereo is 1/5 of the price of the leather so we divide by 5 2906.63 ÷ 5 = 581.33
there u go! pls give brainliest :D
need help please again
Answer:
7 hours
Step-by-step explanation:
d=rt
d is distance
r is speed
t is time
here we need to find (t)
so d/r is t
so t is 455/65
t is 7
Need help with this geometric question ASAP, Thank you
Answer: 15
Step-by-step explanation:
Answer for brainliest
25 X 1 =
;)
The answer is 25
25x1 is 25
anything multiplied by 1 Is itself
Find P (Freshman(Girl) Hint: P(A and B)
P(B)
Classroom of Students
Boys Girls
Freshman 4 4 8
Sophomore 5 7 12
Junior 2 3 5
Senior 1
4 5
12 18
Reduce your fraction to lowest terms.
Enter the number that belongs in the green box.
Answer:
[tex]\sf \dfrac29[/tex]
Step-by-step explanation:
From the table:
Total number of Girls = 18Total number of students = 30Total number of Girls who are Freshman = 4[tex]\sf Probability \ of \ an \ event \ occurring = \dfrac{Number \ of \ ways \ it \ can \ occur}{Total \ number \ of \ possible \ outcomes}[/tex]
[tex]\sf \implies P(Girl)=\dfrac{18}{30}[/tex]
[tex]\sf \implies P(Freshman \cap Girl)=\dfrac{4}{30}[/tex]
[tex]\begin{aligned}\sf P(Freshman|Girl)& = \sf\dfrac{P(Freshman \cap Girl)}{P(Girl)}\\\\ & = \sf \dfrac{4}{30} \div \dfrac{18}{30}\\\\ & \sf=\dfrac{4}{30} \times \dfrac{30}{18}\\\\ & = \sf \dfrac29\end{aligned}[/tex]
help me please. either one is fine.
PLEASE HELP I WILL GIVE BRAINLIEST
Answer:
65 degrees
Step-by-step explanation:
The angles will sum up to 360, just do 360 - all known angles
360 - 90 - 128 - 77 = 65
Answer:
Step-by-step explanation:
Sum of all angles is 360 degrees
Let the measure of angle M equal x.
x+90+77+128=360
x=65
Measure of angle M is 65 degrees
the figure represent 7/9 0f a full circle Find the measure of the marked central angle
Step-by-step explanation:
tbh I don't know I need help with that too please like this comment
The measure of the marked central angle of the sector will be 280°.
What is the arc length of the sector?Let r is the radius of the sector and θ be the angle subtended by the sector at the center. Then the arc length of the sector of the circle will be
Arc = (θ/2π) 2πr
The figure addresses 7/9 of a complete circle. Then the arc length of the circle will be given as,
Arc / P = 7/9
Simplify the equation, then we have
(θ/2π) 2πr / 2πr = 7/9
θ/2π = 7/9
θ = 14π / 9
θ = 280°
The central angle of the sector will be 280°.
More about the arc length of the sector link is given below.
https://brainly.com/question/15955580
#SPJ2
Help me please with math for points
Answer:
The answer is 72
Step-by-step explanation:
because you take the 8 times it by the 9
9×8=72 square³
Which of the following is the solution to the equation 4 over 5 times n = 20
N = 4
N= 12
N = 16
N = 25
Answer:
(d) N = 25
Step-by-step explanation:
The solution to a one-step linear equation can be found by performing the inverse of the operation that is performed on the variable.
(4/5)N = 20
(5/4)(4/5)N = (5/4)(20) . . . . . multiply by the inverse of the coefficient
N = 25 . . . . . simplify
the table of value shows a linear relationship
Answer:
I believe your answer is A
Step-by-step explanation:
Rise is over run, the run (x) is increasing by five but, the rise (y) is decreasing by 8 so the answer would be -8/5
Hope this helps! :)
evaluate the expression 4 3x when x is 2
Someone pls
.
A
A
A
A
A
A
S
Answer:
7
Step-by-step explanation:
Degree of a polynomial is a variable's highest exponent
In this expression the degree is 7
Answer:
7
Step-by-step explanation:
If you used
P.E.M.D.A.S
Brainly please I worked so hard for this answer
PLEASE HELP PLEASE HELP
The value of x is 6. What is the value of y ?
Answer: y = 4.5
scale factor = 4/3
2. On the first day of a month, Leann's savings account had $176. During the
month, Leann deposited $198 and spent $160 of her money. What was
Leann's account balance at the end of the month?
⚫️-138 dollars
⚫️534 dollars
⚫️214 dollars
⚫️-182 dollars
write THREE equivalent fractions for the following fractions:
25/50 = ___ = ___ =____
Answer:
25/50 = 5/10 = 1/2
Step-by-step explanation:
I hope it will be helpful
Answer:
25/50 = 5/10 = 1/2Hooe this helps you :)Brand X rice sells for $70 per kg. Brand Y rice sells for $20 per 400 g. Both brands have similar qualities 8 . Which brand is the better buy? Why do you think so?
Answer:
Brand Y would have a better deal.
Step-by-step explanation:
Step 1. There are 1,000 grams in 1 kilogram. Knowing this, you can see that it would be $70 for 1,000 grams of rice and $20 for 400 grams of rice.
Step 2. You would have to do 70 divided by 1000 (0.07) and 20 divided by 400 (0.05) to see which has the better deal.
Step 3. Brand X is 7 cents per grain and Brand Y is 5 cents per grain, making Brand Y the better deal. I hope that this helps! :)
True or False: In an exponential regression, the data points tend to increase in one direction and flatten out in the other direction.
Answer:
T
Step-by-step explanation:
The regression line is flat when there is no ability to predict whatsoever. The regression line is sloped at an angle when there is a relationship. The extent to which the regression line is sloped, however, represents the degree to which we are able to predict the y scores with the x scores
The mean of 5 different numbers is 6 and the mean of 4 different
numbers is 15. Find the mean of 9 numbers. Please answer fast as possible.
Given the equation of a circle, x^2 + y^2 - 6x + 2y + 1 = 0, find the coordinates of the center and the length of the radius
Answer:
Center: (3,-1)
Radius: 3
Step-by-step explanation:
Given:
[tex]\displaystyle \large{x^2+y^2-6x+2y+1=0}[/tex]
First, we have to convert the following standard circle equation to this:
[tex]\displaystyle \large{(x-h)^2+(y-k)^2=r^2}[/tex]
where h is horizontal shift, k is vertical shift and r is radius.
That means we have to complete the square for both x-term and y-term.
Rearrange the equation:
[tex]\displaystyle \large{x^2-6x+y^2+2y+1=0}\\\displaystyle \large{(x^2-6x)+(y^2+2y+1)=0}[/tex]
For [tex]\displaystyle \large{y^2+2y+1}[/tex], can be converted to perfect square as [tex]\displaystyle \large{(y+1)^2}[/tex]. Hence:
[tex]\displaystyle \large{(x^2-6x)+(y+1)^2=0}[/tex]
For the x-terms, we have to find another value that can complete the square. We know that [tex]\displaystyle \large{(a\pm b)^2 = a^2 \pm 2ab + b^2}[/tex].
For [tex]\displaystyle \large{x^2-6x}[/tex] can be [tex]\displaystyle \large{x^2-2(x)(3)+3^2 \to x^2-6x+9}[/tex]. So our another value is 9.
[tex]\displaystyle \large{(x^2-6x+9-9)+(y+1)^2=0}[/tex]
From above, we add -9 because the original expression isn’t actual perfect square.
Separate -9 out of [tex]\displaystyle \large{x^2-6x+9}[/tex]:
[tex]\displaystyle \large{(x^2-6x+9)-9+(y+1)^2=0}[/tex]
Transport -9 to add another side:
[tex]\displaystyle \large{(x^2-6x+9)+(y+1)^2=9}[/tex]
Complete the square:
[tex]\displaystyle \large{(x-3)^2+(y+1)^2=9}[/tex]
Finally, we have our needed equation to find radius and center. The coordinate of center is defined as the point (h,k) from [tex]\displaystyle \large{(x-h)^2+(y-k)^2=r^2}[/tex] and the radius is defined as r.
Hence, from the equation:
The coordinate of center is (3,-1) with radius equal to 3.
Find the surface area of the cube in square feet.
Answer:
The answer is 2/3 or 0.67 square foot.
Step-by-step explanation:
Given;Length (l) = 1/3 ftTo Find;Surface area of cubeFormula;Area = 6l²Now,
A = 6l²
A = 6 × (1/3)² ft
A = 6 × 1/9 ft
A = 6/9 ft
A = 2/3 square foot
Thus, The surface area of cube is 2/3 or 0.67 square foot.
The area of South America is approximately 1.78 × 107 square kilometers. Its population is approximately 3.50 × 108 people. What is the approximate population density (people per square kilometer) of South America? Write your answer in standard form. If necessary, round your answer to the nearest hundredth.
A: 19.66 people/km^2
B: 1.97 × 10^15 people/km2
C: 5.09 people/km^2
D: 1.97 × 10^1 people/km^2
Answer: 19.66 people/km^2, A
Step-by-step explanation:
The population density will be equal to 82.96 people/km2.
The correct option is B.
What is an expression?Expression in maths is defined as the collection of numbers variables and functions by using signs like addition, subtraction, multiplication, and division.
Numbers (constants), variables, operations, functions, brackets, punctuation, and grouping can all be represented by mathematical symbols, which can also be used to indicate the logical syntax's order of operations and other features.
here, we have,
Given that the area is 1.78 × 10⁷ km² with 3.50 × 10^8 people.
The population density will be calculated as below:-
Density = people / km² = ( 3.50 × 10^8 ) / ( 1.78 x 10⁷ )
Density =19.66
Density = 19.66 people/km²
Therefore, the population density will be equal to 82.96 people/km2. The correct option is A.
To know more about an expression follow:
brainly.com/question/9699102
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Find angles B, E, C, and D, given that angle m A=140° and m F=130°.
*Picture is not drawn to scale*
Answer:
Angle B=40 degrees
Angle C= 90 degrees
Angle E=50 degrees
Please Mark Brainliest
these answer- I am sure they ar correct
The population of a city increased from 21,400 to 27,700 between 2007 and 2016. Find the change
of population per year if we assume the change was constant from 2007 and 2016.
Answer:
700
Step-by-step explanation:
2016 - 2007 = 9
27,700 - 21,400 = 6300
6300 / 9 = 700.
The ratio of blue jays to Robin's was 6 to 7. If there were 84 Robins, how many blue jays were there?
Answer:
72
Step-by-step explanation:
Since the ratio of blue jays to robin's was 6 to 7 then if there were 84 robins how many blue jays were there.
6 to 7 can also be express as 6/7
Thus, we can set up a proportion
6/7 = x/84
Now, we have to solve for x
x = 72
Hence, if there were 84 robin there would be 72 blue jays.
~lenvy~