1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
tankabanditka [31]
3 years ago
12

Y varies directly with x, and y = 5 when x = 4. What is the value of x when y = 8?

Mathematics
1 answer:
Tomtit [17]3 years ago
7 0
As y varies directly with x, there is a proportionality constant. As x increases by that certain constant, y also increases. We equate:
y = kx
where k = proportionality constant.
Given the condition, y = 5 when x = 4, then we solve for k:
5 = k(4)
k = 5/4 or 1.25
When y = 8, then
8 = (5/4)(x)
x = 8/(5/4) = (8)(4/5) = 32/5 or 6.4 (ANSWER)
You might be interested in
In a Harris poll of 514 human resource professionals, 90% said that the appearance of a job applicant is most important for a go
Licemer1 [7]

Answer: The interval is 0.9 ± 0.0259 and margin of error is 0.0259

Step-by-step explanation: <em>Confidence interval for a proportion in one sample</em> is the estimate of the proportion of a population. It is calculated following the next steps:

1) Find the proportion p=\frac{x}{n}, in which x is the number of people with the desired condition. In our case, p=0.9;

2) Calculate margin of error, i.e.:

z\sqrt{\frac{p(1-p)}{n}}

z is z-score, which for a 95% confidence, equals 1.96;

Substituting with the data given:

1.96(\sqrt{\frac{0.9(1-0.9)}{514}}) = 0.0259

3) Write: p ± z\sqrt{\frac{p(1-p)}{n}}

In our case, the interval will be 0.9 ± 0.0259.

<u><em>Margin</em></u><em> </em><u><em>of</em></u><em> </em><u><em>error</em></u> is the random sampling error in the results of a survey, i.e.,it shows you how far your result will be from the real value. For the Harris poll, margin of error is 0.0259

7 0
3 years ago
What is not a description of slope?
Gelneren [198K]

Answer:

Option (d) is wrong.

Step-by-step explanation:

Slope is:

  • rise over run
  • The rate of change of a line
  • Change in y over the change in x
  • <em><u>The ratio of vertical change  to the horizontal change. </u></em>

It can be given by mathematically as follows :

m=\dfrac{y_2-y_1}{x_2-x_1}\\\\\text{and}\\\\m=\dfrac{dy}{dx}

Hence, the option which is not a description of slope is (d) "the ratio of horizontal change compared to vertical change"

7 0
3 years ago
Can someone help me with this! It would be much appreciated!!
love history [14]

Answer:

1. parallelogram

2. trapezoid

3.rectangle

4. parallelogram

5. trapezoid

6. rhombus

7.rectangle

8. rhombus

3 0
3 years ago
One number is five more than a second number. The product of the numbers is 3,300. Find the two numbers
krek1111 [17]
A = b+5
ab = 3300
(b+5)b = 3300
b² +5b -3300 = 0  (quadratic formula)
b=55
a=60      (by first relation)
7 0
3 years ago
find the slope between each pair of points please help with these three questions and i’ll mark the brain thing !
madam [21]

(If It's a number like this: 8/9 then it's a fraction)

Answer:

<h2><em><u>9. -2/6</u></em></h2><h2><em><u>10. -6/-10</u></em></h2><h2><em><u>11. 3/4</u></em></h2>

Step-by-step explanation:

Yay, I love doing these!

9.} 6 - 8 and 4- -2= -2/6

10.} 3 - 9 and -1 - 9= -6/-10

11.} -1 - -7 and 5 - -3= 6/8 simplify it by 2= 3/4

5 0
3 years ago
Other questions:
  • What is 8x8x8x8x8x8x8 using an exponent
    11·2 answers
  • If it takes 15 minutes to load 3 racks of buns jow many hours will it take to load 36vracks
    15·1 answer
  • The sum of a number and its reciprocal is equal to 4 times the reciprocal. Find the number.
    6·1 answer
  • Could use some help.
    13·1 answer
  • What is the relationship between sides and angles for each type of triangle? a) isosceles b) equilateral
    6·2 answers
  • A letter of the alphabet is chosen at random. Find the probability that the letter selected is a vowel.
    8·1 answer
  • What is the LCM for (x + 3)2(x – 2) and (x + 3)(x2 – 16)? A. (x + 3) B. (x + 3)(x – 2)(x – 16) C. (x + 3)3(x – 2)(x2 + 16) D. (x
    10·1 answer
  • 18. The price of 1 box of popcorn and 1 drink together is The price of popcorn and 1 drink together is What is the cost of 1 dri
    10·2 answers
  • Find the value of X ​
    6·1 answer
  • Helpppppppppppp meeeeeeeeee
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!