Half time of krypton 91 = 10s
this means, it reduces to half of the remaining in every 10s
So, In 10 sec , the mass remaining will be :
3/2 = 1.5
After 20 sec, the mass remaining will be :
0.75 g
After 30 sec, the mass remaining will be :
0.375
After 40 sec, the mass remaining will be :
0.1875 g
After 50 sec, the mass remaining will be :
0.09375 g
After 1 minute, the mass remaining will be:
0.046975 g
Use quadratic regression to find a function that fits the following points. (-2,-16), (3,11), (0,2).
Answer:
y = -1.2x² +6.6x +2
Step-by-step explanation:
The quadratic regression function of a calculator or spreadsheet can do this for you. The resulting function is ...
y = -1.2x² +6.6x +2
_____
If you want to do this by hand, put the given (x, y) values into the formula ...
ax² +bx +c = y
and solve the resulting system of equations.
The third point tells you c=2, so you can simplify the system of equations to ...
a(-2)² +b(-2) +2 = -16 ⇒ 4a -2b = -18 ⇒ 2a -b = -9
a(3)² +b(3) +2 = 11 ⇒ 9a +3b = 9 ⇒ 3a +b = 3
Adding these equations together gives ...
(2a -b) +(3a +b) = (-9) +(3)
5a = -6 . . . . . . . . simplify
a = -1.2 . . . . . . . divide by 5
b = 3 -3a = 3 -3(-1.2) = 6.6 . . . . from the second equation
Now we know the coefficients are a=-1.2, b=6.6, c=2, so the function is ...
y = -1.2x² +6.6x +2
The lines represented by the equations y + 3/2x = -6 and 3y – 2x = -24 are
parallel
neither parallel nor perpendicular
perpendicular
the same line
Answer:
Neither Parallel nor Perpendicular
Step-by-step explanation:
Convert 3y - 2x = -24 to slope - intercept form
3y - 2x = -24
3y = -24 + 2x
3y = 2x - 24
y = 2/3x - 8
They are neither parallel or perpendicular
Parallel lines have the same slope, but these are different
Perpendicular lines have the opposite inverse (negative reciprocal) slope, but these are just reciprocals
-Chetan K
Please help, this is timed :))
This is the right answer
Which of the following is not true about a square?
Answer:
All its sides are of equal lengths.
and
It has opposite parallel sides.
Step-by-step explanation:
solve for x
5x - 2 = 6
give your answer as an improper fraction in its simplest form
Answer:
x= 8/5
Step-by-step explanation:
add 2 to both sides
5x=8
divide both sides from 5
x=8/5
The miller’s are comparing babysitting services for their two children. the babysitters block charges a rate of $15 an hour per child plus an initial fee of $25 per household. super sitters charges a flat rate of $20 an hour per child. for …. hours of service both babysitting services would cost the same
Answer:
2.5 hours
Step-by-step explanation:
BB = 25 + (15x)2
SS = (20x)2
25 + 30x = 40x
10x = 25
x = 2.5
Answer:
5 hours
Step-by-step explanation:
15 times 5 is 75 plus 25 is 100
20 times 5 is also 100
Micah’s bill for dinner was $35.50. He left the server an 18% tip. How much money did Micah leave for the tip?Enter the correct answer in the box.
Answer:
$41.89
Step-by-step explanation:
100%=35.50
1%=0.3550
18%=6.39
$35.50+6.39=$41.89
Answer: 49.89 percent
Step-by-step explanation:
Be a good boy
Ezra and Benji are playing the game with Harrison. After Ezra doubles his hand's value, he has a total of -12.5 points. What was his hand's value before
he doubled it?
A new video streaming and renting company Webflix claims it is better than its competitors. They charge $3.00 per month plus $1.25 per rental of new movie releases. A close competitor refutes the claims of Webflix and stated that they are actually better than its competitors. Zulu charges $4.00 per month plus
$1.00 per rental of new movie releases.
a) If you rent 7 movies, which streaming service would cost more? Explain/show your reasoning
b) Write a system of equations representing the total costs of the two streaming companies based on x
movie rentals.
c) How many movie rentals would it take for the streaming services to cost the same? Explain/show
your reasoning
d) Make an argument on which streaming service is the better cost.
Answer:
A
Step-by-step explanation:
I I think that's the answer
(C) c varies directly as a and inversely as b. If c= 15 when a = 18 and b = 40, find c when a = 36, and b = 25. = с
Answer:
c = 48
Step-by-step explanation:
Given c varies directly as a and inversely as b then the equation relating them is
c = [tex]\frac{ka}{b}[/tex] ← k is the constant of variation
To find k use the condition c = 15 when a = 18 and b = 40 , then
15 = [tex]\frac{18k}{40}[/tex] ( multiply both sides by 40 )
600 = 18k ( divide both sides by 18 )
[tex]\frac{600}{18}[/tex] = k
[tex]\frac{100}{3}[/tex] = k
c = [tex]\frac{100a}{3b}[/tex] ← equation of variation
When a = 36 and b = 25 , then
c = [tex]\frac{100(36)}{3(25)}[/tex] = [tex]\frac{3600}{75}[/tex] = 48
Put the following equation of a line into slope-intercept form, simplify all fractions 8x + 20y = -120
Hello there! :)
8x+20y=-120
We want to put this equation into slope-intercept form (y=mx+b)
First, let's move 8x to the right side:
20y=-120-8x
Now, we divide both sides by 20 to isolate y:
y=-8/20-6
Simplify the fraction:
y=-2/5-6
Hence, that's our equation. Hope it helps you! (:
If you have any queries, feel free to ask me! :)
~A smiley teen who adores helping others
[tex]MagicalNature[/tex]
SUPER EASYYYYYYYYYYYYYYYY
Hello, hope you are having a nice day.
t^3*t^9
When we multiply numbers with the same base, we add the powers.
t^12
That's the answer. Hope it helps
Ask me if you have any queries.
[tex]MagicalNature[/tex]
Good luck.
PLZ HELP FAST!!
Alson earns a 7% commission on every sale he makes. Let a represent the commission Alson earns.
Damon earns the same commission as Alson. Let d represent the commission Damon earns.
Stefan does not earn the same commission as Alson. Let s represent the commission Stefan earns.
Which statement is true?
d = s
a = s
a = d
a ≠ d
Answer:
a = d
Step-by-step explanation:
I recommend writing the math out.
a = d ≠ s
d can not be equal to s, the same why a can not be equal to s. a and d are the same. a is equal to d, so it can not be a ≠ d. By process of elimnation, that leaves us with a = d
What are the roots of the function f(x) = x2 + 2x – 1? a. x = ± √ _ 2 b. x = − 1 ± √ _ 2 c. x = 2 ± √ _ 2 d. x = 1 ± √ _ 2
Step-by-step explanation:
Root of the function, where y = 0
f(x) = x² + 2x - 1
0 = x² + 2x - 1
x² + 2x - 1 = 0
x² + 2x = 1
x² + 2x + 1 = 1 + 1
(x + 1)² = 2
x + 1 = ±√2
x = -1 ± √2
Roots → x = -1 ± √2
Tell whether the given value is a solution of the inequality.
Answer:
Step-by-step explanation:
8p < -3
if p = -2
8* -2 < -3
-16 < -3 TRUE so p= -2 is a solution to the inequality 8p < -3
Mary is 4 years older than her sister Dawn.
In total the sisters have a combined age of 32.
Form an equation to show this. How old is Mary?
3.(08.01 MC)
Find the length of the base of a square pyramid If the volume is 48 cubic inches and has a height of 9 inches.
O 4 inches
O 8 inches
O 16 inches
0
24 inches
Answer:
4 inches
Step-by-step explanation:
The formula is L=√((3×V)/h)
Of the 32 teachers at Devon's high school, 22 are female. What is the ratio of the number of male teachers to the total number of teachers?
Write your answer as two numbers separated by a colon (for example, 2:3).
Answer:
10:32
Step-by-step explanation:
32-22=10 male teachers
Can someone help me
For the first question = no because no sides matchup
4. On Monday, a department store sold 30 white and blue sweaters in total. If a white sweater is 398 baht, and a blue sweater is 420 baht, the total sales are 12,424 baht. How many sweaters in each color did this department store sell?
The number of white sweaters will be 8 while the number of blue sweaters will be 22.
Let white sweaters be represented by w.Let blue sweaters be represented by bTherefore, the equation to solve the question will be:
b + w = 30 .....i
420b + 398w = 12424 .... ii
From equation i, b = 30 - w
Since 420b + 398w = 12424
420(30 - w) + 398w = 12424
12600 - 420w + 398w = 12424
Collect like terms
- 420w + 398w = 12424 - 12600
-22w = - 176
w = 176/22 = 8
Since b + w = 308
b = 30 - 8 = 22
Therefore, there are 8 white and 22 blue sweaters.
Read related link on:
https://brainly.com/question/25734188
question is in picture
what is 1 + 1
(first gets brainliest)
Answer:
2
Step-by-step explanation:
bet
2x+5=12 i don´t know what the value of x is
Answer: X = 7/2 or 3.5
what percentage of this grid is shaded
how many more squares need to be shaded so that 60% of the grid is shaded?
Answer:
44%, and 4
Step-by-step explanation:
The grid has 5 rows and 5 columns so we have 5*5 = 25 squares.
25 squares represent 100 % of the grid
a) In the grid 11 of the 25 total squares are blue, so if
25 squares are 100%
11 squares will be x%
x= (11* 100) / 25 = 1100/ 25 = 44 %
b) we find the number of squares that gives us 60 %
25 squares are 100%
x squares will be 60%
x= (60*25)/ 100 = 15
The question is " How many more squares " so we have to compare with the 11 given ones in part a)
15 -11 = 4
4 more squares will give 60 % blue grid.
how do you turn radius into cm
Answer:
depending on the question I suggest only converting at the end
sorry if it doesn't help
by the way a cm needs to be times by 100 to become a meter
The ratio of pages Kim reads to
minutes that pass is 10:15. How
many minutes will pass if Kim
reads 40 pages?
Answer:
40:60
Step-by-step explanation:
heres if u need the work,
10:15
40:?
10x4=40
15x4=60
40:60
Answer
she will read for 1 hour
Step-by-step explanation:
:)
A shirt is 20% off the sticker price of $34. How much is the discount?
Answer:
Step-by-step explanation:
you would pay is 34 - 6.8 = 27.2 dollars. hope it helps bye :)
Answer asap pleaseeeee
Answer:
I am not certified because I also struggle with these but-
it might be
A. t = -5h-4
Step-by-step explanation:
For the answer A in the paragraph it states that the temperature was 4 degrees BELOW 0 meaning we shall put as -4° and each HOUR it keep going down 5 degrees so I would suppose it would be answer A.
Help me please I need to pass this class
Answer:
The answer is C
Step-by-step explanation:
I know this because if you 5 plus 3 is 8 right not the other ones so if you just add zero's it will be 50 plus 30 and then that will equal 80 so it is for every 5 question's he got 3 wrong.
Hope this helps ('o')
Given : In the recent maths test, Jeremy answered 48 questions correct out of 80 total questions. Which statement is correct ?
Solution :
As we know that total no. of questions is 80
Now, as per the options we get 80/5 = 16
However the third option seems to be the accurate as 3(16) = 48
So, we get to know that option C is correct
Out of every 5 questions, Jeremy answered 3 correctly.Can someone please help? I'll give brainliest if correct
Answer:
vertex = (7, - 2 )
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
y = x² - 14x + 47
Using the method of completing the square
add/subtract ( half the coefficient of the x- term)² to x² - 14x
y = x² + 2(- 7)x + 49 - 49 + 47
= (x - 7)² - 2 ← in vertex form
with vertex = (7, - 2 )