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
Schach [20]
2 years ago
14

Y is directly proportional to square root of x If y=56 when x=49 find, y when x=81

Mathematics
1 answer:
STALIN [3.7K]2 years ago
7 0

\qquad \qquad \textit{direct proportional variation} \\\\ \textit{\underline{y} varies directly with \underline{x}}\qquad \qquad \stackrel{\textit{constant of variation}}{y=\stackrel{\downarrow }{k}x~\hfill } \\\\ \textit{\underline{x} varies directly with }\underline{z^5}\qquad \qquad \stackrel{\textit{constant of variation}}{x=\stackrel{\downarrow }{k}z^5~\hfill } \\\\[-0.35em] \rule{34em}{0.25pt}

\stackrel{\begin{array}{llll} \textit{"y" directly}\\ \textit{proportional to }\sqrt{x} \end{array}}{y = k\sqrt{x}}\qquad \textit{we know that} \begin{cases} y = 56\\ x = 49 \end{cases}\implies 56=k\sqrt{49} \\\\\\ 56=7k\implies \cfrac{56}{7}=k\implies 8=k~\hfill \boxed{y=8\sqrt{x}} \\\\\\ \textit{when x = 81, what is "y"?}\hfill y=8\sqrt{81}\implies y=8(9)\implies y=72

You might be interested in
You want to place stone pavers around the edge of your concrete patio. The patio is 12 ft wide by 14 ft long and each stone pave
Harlamova29_29 [7]

The number of stone pavers needed to go round the patio is 3.

<h3>What is the number of stone pavers needed to go round the patio?</h3>

The first step is to determine the perimeter of the concrete patio.

Perimeter : 12 + 12 + 14 = 38 feet

Number of stone pavers needed to go round the patio : perimeter of the patio / length of each stone paver

38 / 14 = 3

To learn more about the perimeter of a rectangle, please check: brainly.com/question/3205029

#SPJ1

4 0
2 years ago
Kiran's mother gets a restaurant bill for $25. She has a coupon for 15% off. After the
PtichkaEL [24]

Answer:

$25.50

Step-by-step explanation:

So we have a 15% off coupon. We can multiply 25×.85 to find our new price.

Our total is now $21.25

Now to find the tip do $21.25 +(.2 × 21.25)

*The .2 is 20 percent of our discount price.*

We then get $25.50

8 0
3 years ago
11 times a number increased by 2 is the same as 6 more than 9 times the number. Find the number.
7nadin3 [17]
11x+2 = 9x+6. Subtract 2 from both sides. 11x = 9x+6. subtract 9x from both sides. 2x = 4, divide both sides by 2. x = 2. Substitute the x with 2 and check to see it it works. The numbers should equal each other.
8 0
3 years ago
What is 36/63 in simplest form?
leonid [27]
36/63 in its simplest form is 4/7

Have a great day! =)
3 0
2 years ago
Read 2 more answers
At 107°F, a certain insect chirps at a rate of 92 times per minute, and at 113°F, they chirp 116 times per minute. Write an equa
dsp73

Answer:

The equation in slope-intercept form that represents the situation is y=0.25*x + 84 where y represents the temperature in ° F and x the number of chirps per minute.

Step-by-step explanation:

A linear equation can be expressed in the form y=m*x + b. In this equation, x and y are coordinates of a point, m is the slope and b is the y coordinate of the y-intercept. Since this equation describes a line in terms of its slope and its y-intercept, this equation is said to be in its slope-intercept form.

When there are two points of a line (x1, y1) and (x2, y2), the slope is determined by the quotient between the difference of the ordinate of these two points and the difference of the abscissa of the same points. This is:

m=\frac{y2-y1}{x2-x1}

Having a point on the line, you can substitute the values ​​of m, x and y in the equation y = mx + b and thus find b.

In this case:

  • (x1, y1): (92, 107)
  • (x2, y2): (116, 113)

So:

m=\frac{113-107}{116-92}

m= 0.25

substituting the values ​​of m, x1 and y1 in the equation y = mx + b you have:

107= 0.25*92 + b

107 - 0.25*92= b

84=b

<u><em>The equation in slope-intercept form that represents the situation is y=0.25*x + 84 where y represents the temperature in ° F and x the number of chirps per minute.</em></u>

3 0
3 years ago
Other questions:
  • 10^-2 x 6^-2 please help
    13·1 answer
  • To find 45% of 72, multiply 45/100×72.
    15·2 answers
  • On the class field trip, there were 4 teachers and 35 students. What is the ratio of students to teachers on this trip?
    9·1 answer
  • Can someone help me and explain step by step
    13·1 answer
  • Please help and show the work to this page !!
    10·2 answers
  • A cube has its six sides colored red, white, blue, green, yellow, and violet. It is assumed that these six sides are equally lik
    7·1 answer
  • 3/5 of $40 restraunt bill
    8·1 answer
  • A cartoon contains 5 1/2 cups of juice. One serving is 3/4 of a cup. How many servings of juice are in the cartoon?
    9·2 answers
  • I need help with this important question it's for a important grade​
    15·1 answer
  • Equation: 7(2j + 3 + 2j).
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!