Answer:
[tex]x=27[/tex]
[tex]y=-6[/tex]
Step-by-step explanation:
substitute in values
[tex]x=21-y[/tex]
[tex](21-y)+3y=9[/tex]
[tex]21+2y=9[/tex]
[tex]2y=-12[/tex]
[tex]y=-6[/tex]
[tex]x+(-6)=21[/tex]
[tex]x=27[/tex]
Determine the variables tested in each of the following experiments. If applicable, determine and identify any positive or negative controls. A study is being done to test the effects of habitat space on the size of fish populations. Different sized aquariums are set up with six goldfish in each one. Over a period of six months, the fish are fed the same type and amount of food. The aquariums are equally maintained and cleaned throughout the experiment. The temperature of the water is kept constant. At the end of the experiment, the number of surviving fish are surveyed. A. Independent Variable: B. Dependent Variable: C. Controls:
Answer:
Independent Variable- size of aquariums
Dependent variable - number of surviving fish
Controls: nil
Step-by-step explanation:
In every experiment, the independent variable is manipulated and its effect on the dependent variable is observed as certain factors are kept constant.
In this study, the independent variable is the size of the aquariums. As this factor is manipulated, the number of surviving fish (dependent variable) changed accordingly. There was no mention of a control group in the experiment.
However, temperature, amount of food and type of food were held constant for all the experimental groups.
Alright, -3r + 4(-3r + 2) = 53 how do I break it down and solve??
Answer:
r = -3
Step-by-step explanation:
-3r + 4(-3r +2) = 53
-3r + -12r + 8 = 53
-8 -8
-3r + -12r = 45
-15r = 45
Divide both sides by -15 to get
r = -3
Answer:
r = -3
Step-by-step explanation:
expand 4(-3r+2)
= -12r+8
add similar variables
= -15r+8=53
subtract 8 from both sides
= -15r+8-8=53-8
simplify
= -15r=45
divide 45 by -15
= -3
what is Hola, soy el chico nuevo de la clase y me gustan los coches, in english, and what is 100x100x38
Answer:380000
Step-by-step explanation:
Answer:
Hi, I'm the new kid in class and I like cars AND 380000
Step-by-step explanation:
An object is moving at a speed of 6 miles per month. Express this speed in feet per hour
Answer:
44 feet/hour
Step-by-step explanation:
6mi/month(5280ft/1mi)(1month/30days)(1day/24hrs)
Assuming the month has 30 days, object moves at 44 feet/hour. You want all the units to cancel till you get the ones you need, in this case feet/hr.
You and your friend start a typing class at the same time. You measure your speed weekly in words per minute (WPM) on a class chart. If the trend continues, after how many weeks can you expect to type as quickly as your friend? What will that WPM be?
A. 6 weeks;28 WPM
B. 6 weeks; 31 WPM
C. 7 weeks;31 WPM
D. 7weeks;34 WPM
Answer:
The correct answer is 7 weeks 34 WPM
Step-by-step explanation:
The number of weeks and words typed will be D. 7weeks;34 WPM
Based on the information given, the formula to calculate my words per minutes = 13 + 3n
The formula to calculate my friend's words per minutes = 20 + 2n
Therefore, we'll equate both equations together and this will be:
13 + 3n = 20 + 2n
Collect like terms
3n - 2n = 20 - 13
n = 7.
Therefore, the WPM will be:
= 13 + 3n
= 13 + 3(7)
= 13 + 21
= 34
The number of weeks and words typed will be 7weeks;34 WPM
Read related link on:
https://brainly.com/question/18314140b
A sample has an n of 99. What is the df of this sample?
Answer: The correct answer is: " 98 " .
______________________________________
Step-by-step explanation:
______________________________________
In this case, "degrees of freedom" , or "df":
"df" = n - 1 ;
in which: "n = the numeric value of the sample size."
Given: "n = 99" ; we can plug that value into the formula:
"df" = n - 1 = 99 - 1 = 98 .
______________________________________
describe how you can
identify if two lines are coinciding using substitution, elimination, and/or
graphing methods? *
To use substitution to identify if two lines intersect,
1. Rearrange one of the two given equations so that only one variable is on one side of the equation with all other values on the other side of the equation. (if needed)
2. Plug this new equation into the other (in place of a variable)
3. Solve the equation to get the answer of one of the variables
4. Plug this variable into one of the two original equations and solve for the second variable (if needed)
5. Plug both variables back into one of the original equations. If both sides of the equation are equal, the two lines do coincide.
Example:Equation 1: 2x+3y=9
Equation 2: x+8=3
1. Rearrange equation 2
x+8=3
x=3-8
x=-5
2. Plug -5 into the first equation as x
2x+3y=9
2(-5)+3y=9
3. Solve this equation
-10+3y=9
3y=9+10
3y=19
y=[tex]\frac{19}{3}[/tex]
4. Plug x and y back into the first equation
2x+3y=9
2(-5)+3([tex]\frac{19}{3}[/tex])=9
-10+19=9
9=9
Therefore, these two lines do coincide. The point of intersection is (-5,[tex]\frac{19}{3}[/tex]).
Using Elimination:To use elimination to identify if two lines intersect:
1. Multiply one or both of the equations by a factor so both equations have either an x or y coefficient that are equal or opposite of each other (if needed)
2. Add or subtract the two equations to get rid of one variable
3. Solve this new equation for a variable
4. Substitute this variable into one of the two equations to solve for the other
5. Plug both variables back into one of the equations. If both sides are equal, the two lines do coincide.
Example:Equation 1: 2x+3y=4
Equation 2: 4x+2y=3
1. For this specific system of equations, we would multiply the first equation by 2.
2x+3y=4
4x+6y=8
Notice how now, both equations have 4x in them, so we can subtract them:
2. Subtract the new equation from the second original equation
4x+6y=8
- 4x+2y=3
4y=5
3. Solve
4y=5
y=[tex]\frac{5}{4}[/tex]
3. Substitute y back into the first equations (any of the two equations will work) to solve for x
2x+3y=4
2x+3([tex]\frac{5}{4}[/tex])=4
2x+[tex]\frac{15}{4}[/tex]=4
2x=4-[tex]\frac{15}{4}[/tex]
2x=[tex]\frac{16}{4}[/tex]-[tex]\frac{15}{4}[/tex]
2x=[tex]\frac{1}{4}[/tex]
x=[tex]\frac{\frac{1}{4} }{2}[/tex]
x=[tex]\frac{1}{4}*\frac{1}{2}[/tex]
x=[tex]\frac{1}{8}[/tex]
4. Plug both variables back into the first equation (either equation works)
2x+3y=4
2([tex]\frac{1}{8}[/tex])+3([tex]\frac{5}{4}[/tex])=4
[tex]\frac{1}{4}[/tex]+[tex]\frac{15}{4}[/tex]=4
[tex]\frac{16}{4}[/tex]=4
4=4
Since the left side equals the right side, the two lines are coinciding.
Using Graphing Methods:To use graphing methods to identify if two lines coincide, we would just have to graph the line and identify if the two lines meet at a point of intersection/overlap each other.
I hope this helps!
Two shooters, Rodney and Philip, practice at a shooting range. They fire rounds each at separate targets. The targets are marked with circles and each bullet hitting a particular circle gets them a particular number of points. rounds are selected at random. The sample mean scores of Rodney and Philip are and , respectively. And, their variances are and , respectively. The standard error of the difference between their mean scores is . 13. (Round your answer to two decimal places.) The 95% confidence interval for the difference between the mean scores of Rodney and Philip is
Complete Question
Answer:
a
[tex]SE = 0.66}[/tex]
b
[tex] -3.29 < \mu_1 - \mu_2 < -0.70[/tex]
Step-by-step explanation:
From the question we are told that
The sample size is n = 60
The first sample mean is [tex]\= x _1 = 8[/tex]
The second sample mean is [tex]\= x _2 = 10[/tex]
The first variance is [tex]v_1 = 0.25[/tex]
The first variance is [tex]v_2 = 0.55[/tex]
Given that the confidence level is 95% then the level of significance is 5% = 0.05
Generally from the normal distribution table the critical value of [tex]\frac{\alpha }{2}[/tex] is
[tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]
Generally the first standard deviation is
[tex]\sigma_1 = \sqrt{v_1}[/tex]
=> [tex]\sigma_1 = \sqrt{0.25}[/tex]
=> [tex]\sigma_1 = 0.5[/tex]
Generally the second standard deviation is
[tex]\sigma_2 = \sqrt{v_2}[/tex]
=> [tex]\sigma_2 = \sqrt{0.55}[/tex]
=> [tex]\sigma_2 = 0.742 [/tex]
Generally the first standard error is
[tex]SE_1 = \frac{\sigma_1}{\sqrt{n} }[/tex]
[tex]SE_1 = \frac{0.5}{\sqrt{60} }[/tex]
[tex]SE_1 = 0.06[/tex]
Generally the second standard error is
[tex]SE_2 = \frac{\sigma_2}{\sqrt{n} }[/tex]
[tex]SE_2 = \frac{0.742}{\sqrt{60} }[/tex]
[tex]SE_2 = 0.09[/tex]
Generally the standard error of the difference between their mean scores is mathematically represented as
[tex]SE = \sqrt{SE_1^2 + SE_2^2 }[/tex]
=> [tex]SE = \sqrt{0.06^2 +0.09^2 }[/tex]
=> [tex]SE = 0.66}[/tex]
Generally 95% confidence interval is mathematically represented as
[tex](\= x_1 -\= x_2) -(Z_{\frac{\alpha }{2} } * SE) < \mu_1 - \mu_2 < (\= x_1 -\= x_2) +(Z_{\frac{\alpha }{2} } * SE)[/tex]
=> [tex](8 -10) -(1.96 * 0.66) < \mu_1 - \mu_2 < (8-10) +(Z_{\frac{\alpha }{2} } * 0.66)[/tex]
=> [tex] -3.29 < \mu_1 - \mu_2 < -0.70[/tex]
How do you do this question?
Answer: Choice A
Explanation:
The sequence converges to a nonzero value, so as n gets very large, the partial sums will grow forever (since we're effectively adding at least 1 to each term regardless how large n gets)
The reason why [tex]s_n[/tex] approaches 1 is because the 1/n term goes to 0 when n gets very large.
scale factor of 2 to 3.5 inches
The linear equation y=-2 is a horizontal line and has an undefined slope true or false
Answer:
False
Step-by-step explanation:
Although it is true that y=-2 is a horizontal line, it does not have an undefined slope. Because it is a horizontal line, it has a slope of 0.
Make w the subject of the relation p=2 (k+w)
Answer:
hope that will help you
w = ( p - 2k )/2
Step-by-step explanation:Hi there !
p = 2(k + w)
2k + 2w = p
2w = p - 2k
w = ( p - 2k )/2
Good luck !
What is the answer for 1/2(2a+4)
Answer:
a+2
Step-by-step explanation:
Answer:
the answer is 3a
Step-by-step explanation:
first you have to think about pemdas which means you have to do parenthises first so 2a+4=6a and then 6a multiplied by 1/2 wich eqauls 3 and then you add the a and now you have you have your final answer.
Select each transformation that carries a square onto itself.
Answer:
b,c,d
Step-by-step explanation:
cus I said so and it's right
Check all of the irrational numbers.
Answer:
√36, √17, 0.33333...., 1.2874....
Step-by-step explanation:
irrational numbers - a number that cannot be exactly expressed as a ratio of two integers.
in 3 1/2 months John collected a debt of $70.00. What was the average amount of debt John collected per month?
Answer:
The average amount of debt John collected per month is $20/ month
Step-by-step explanation:
Given;
total debt collected by John, = $70.00
total number of months, = 3 1/2 months = 7/2 months
The average amount of debt John collected per month is given by;
[tex]Average \ amount \ per \ month = \frac{Total \ amount \ of \ debt}{total \ number \ of \ months} \\\\Average \ amount \ per \ month =\frac{70}{1} *(\frac{2}{7} )\\\\Average \ amount \ per \ month = \$20 \ / month[/tex]
Therefore, the average amount of debt John collected per month is $20/ month
y-intercept of (-2,2) and (-5,-4)
Answer:
-8
Step-by-step explanation:
why does paramcium never die
Answer:
the paracium never dies because it keeps on reproducing
Step-by-step explanation:
the paracium lets say it starts as 1
and then taht 1 divides inti
1/2 and 1/2 and that 1/2 turns into 1
and it keeps on dividing and multiplying
Find the point slope of the line passing through the given points(use the first point (x1,y1)
(-3,4),(2,5)
Answer: y - 4 = 1/5 * (x+3)
Step-by-step explanation:
Please help me solve this I will give u brainlst :)
Choose the justification for each step in the solution to the given equation.
Answer:
addition property of equality, subtraction property of equality, simplified, division property of equality and simplified.
Step-by-step explanation:
Answer:
1 given
2 Combining like terms
3 addition property of equality
4 simplification
5 division property of equality
6 simplification
Step-by-step explanation:
In step 2, the like terms of x and x were combined and simplified to -2x.
In step 3, adding 7 to both sides of the equation to isolate the variable term is justified by the addition property of equality.
In step 4, the constants are combined on each side for simplification.
In step 5, dividing both sides of the equation by -2 to isolate the variable is justified by the division property of equality.
In step 6, simplification results in the solution of x = 4.
NOBODY IS ANSWERING THIS PLEASE PLEASE PLEASE ANSWER ILL LOVE YOU FOREVER
Car A is traveling east at a steady speed of 60 miles per hour after 2 hours, it is 130 miles east of Johnstown. car B is traveling east on the same road. its distance east of Johnstown is represented by the graph.
PLEASE PLEASE PLEASE PLEASE PLEASE PLEASE PLEASE PLEASE HELP
Answer:
D
Step-by-step explanation:
It looks right
sorry if it’s wrong
First, rewrite 17/25 and 7/10
so that they have a common denominator.
Answer:
85/50. 35/50
You would times 17/25 by 5 and you would get 85/50 which would simplify to 1 35/50
you would multiply 7/10 by 5 to get 35/50
quotient of Fraction 3 over 4 divided byFraction 3 over 4 .
Answer:
1
Step-by-step explanation:
The equation would look like this: ¾ ÷ ¾
When dividing fractions, you always flip the second one to receive the reciprocal, so the equation now looks like this: ¾ ÷ 4/3
If you cross simplify, the answer will end up being 1.
Describe the Transformation and CHOOSE ALL THE
CORRECT ANSWERS! (MORE THAN 1 RIGHT
ANSWER).
f(x) = -2(x+3) 3 - 3
Juanita has fewer than 80 coins in her coin collection. She noticed that she can divide her coins evenly into groups of 3, 5, 15, or 25.
How many coins does she have?
Find the LCM
3 = 3 times 1
5 = 5 times 1
15 = 5 times 3
25 = 5 times 5
Because they have one 5 and one 3 in common...
5 times 3 times 5 = 75.
She has 75 coins.
Correct pair
3x+5y=6
4x+2y=-6
Answer:
Step-by-step explanation:
6x + 10y = 12
-20x - 10y = 30
-14x = 42
x = -3
4(-3) + 2y = -6
-12 + 2y = -6
2y = 6
y = 3
(-3, 3)
Need help!!!!!!!!!!!!!!!!!!!!!!!!!!
9514 1404 393
Answer:
a) GH or HG
b) KL
c) YZ or ZY
d) EF
Step-by-step explanation:
A segment or line can be named by naming two points on it in any order. The points naming a line segment are its end points.
A ray is named by first naming its end point, then any other point on the ray.
a) GH or HG
b) KL
c) YZ or ZY
d) EF
when conducting a perpendicular line through point of a line, how can you verify that the line contested is perpendicular?
Answer:
C. Check the intersecting lines with the corner of a piece of paper to ensure the lines create 90° angles. Took the test just now and got it right
Step-by-step explanation:
The value of 2 in 724,638, is 20,00p?
Step-by-step explanation:
total value would be 20,000
place value is hundreds of thousands
that's my opinion cuz I didn't fully understand it but I tried thanks