Two numbers total 31 and have a difference of 11. Find the two numbers

Answers

Answer 1

Answer:

let 2 no. be x and y

x+y=31 ..... (1)

x-y=11 .........(2)

from (1)

x=31-y ..........(3)

putting (3) in (2)

31-y-y=11

-2y=11-31

-2y=-20

2y=20

y=10

Answer 2
31 -11 = 20
20 + 11 = 31
The Two numbers are 20 & 11

Related Questions

The cost of three pants and four shirts is $68.45 if a pant costs $6.85 more than a shirt find the cost of a pant and a shirt estimate to the nearest whole number.

Answers

Which of the following statements is generally true about change in the workplace ? a ) Most people accept change easily . b) Smart companies can avoid change altogether. c) Change in the workplace fairly infrequently d) Individuals can learn to manage the change in their lives.

Answer:

3 pants are $20.55

4 shirts are $47.9

Step-by-step explanation:

a pant is $6.85 × 3= $20.55

68.45 - 20.55 = $47.9

$47.9 ÷ 4 = $11.98 a shirt

Find area and perimeter of shape but perimeter is not 96

Answers

Perimeter:

We have two straight, congruent sides from the square that are 24 cm, and two semi-circles (or one whole circle).

24 + 24 + 1/2(24pi) + 1/2(24pi)

48 + 12pi + 12pi

48 + 24pi cm

Area:

We have a semi-circle and a square that is missing a semi-circle. Let's find the area of the square minus the semi-circle, then add the additional semi-circle.

Square = 576

Missing semi-circle = 144pi / 2 = 72pi

Semi-circle = 144pi / 2 = 72pi

576 - 72pi + 72pi

576 cm^2

Hope this helps!

write your answer in simplest radical form​

Answers

Answer:

[tex]s=6\sqrt{3}[/tex]

Step-by-step explanation:

In any 30-60-90 triangles, the sides are in ratio [tex]x:x\sqrt{3}:2x[/tex], where [tex]x[/tex] is the side opposite to the 30 degree angle and [tex]2x[/tex] is the hypotenuse of the triangle.

In the given diagram, the hypotenuse is marked as 12 miles. Therefore, the side opposite to the 30 degree angle must be [tex]12 \div 2=6[/tex] miles. The final leg, [tex]s[/tex], must then represent the [tex]x\sqrt{3}[/tex] part of our ratio, hence [tex]\implies \boxed{6\sqrt{3}}[/tex]

Which of the following graphs is described by the function given below?
y = x2 - 6x-7 ​

Answers

Answer:

A

Step-by-step explanation:

We are given the function:

[tex]\displaystyle y = x^2 - 6x - 7[/tex]

And we want to determine its graph.

One of the most important features of a quadratic is its vertex. So, we can start by finding the vertex using the formulas:

[tex]\displaystyle \text{Vertex} = \left(-\frac{b}{2a}, f\left(-\frac{b}{2a}\right)\right)[/tex]

In this case, a = 1, b = -6, and c = -7.

Find the x-coordinate of the vertex:

[tex]\displaystyle x = -\frac{(-6)}{2(1)} = 3[/tex]

Substitute this back into the equation to find the y-coordinate:

[tex]\displaystyle y(3) = -16[/tex]

Therefore, our vertex is at (3, -16).

The only graph whose quadratic's vertex is at (3, -16) is Graph A. Thus, our answer is A.

HELP NEEDED PLEASE :(
Identify the center and the radius of a circle that has a diameter with endpoints at (5, 8)
and (7,6).

Answers

Answer:

Centre is,

((5+7)/2,(8+6)/2)

or, (12/2,14/2)

or, (6,7)

radius is,

[√{(5-7)²+(8-6)²}]/2

= [√(2²+2²)]/2

= [√(4+4)]/2

= [√8 ]= [2√2]/2 = √2

The center of a circle = (6, 7)

the radius of a circle = [tex]\sqrt{2}[/tex] units

What is the distance formula?

"The distance between two points [tex](x_1,y_1),(x_2,y_2)[/tex] is given by  [tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_2)^2}[/tex]"

What is midpoint formula?

"The coordinates of the midpoint of the line segment having endpoints [tex](x_1,y_1),(x_2,y_2)[/tex] is given by [tex]m=(\frac{x_1+x_2}{2} ,\frac{y_1+y_2}{2} )[/tex] "

What is diameter of circle?

"It is the line segment through the center and touching two points on its edge. "

For given question,

The diameter of circle has endpoints at (5, 8) and (7,6).

Let [tex](x_1,y_1)=(5,8),(x_2,y_2)=(7,6)[/tex]

First we find the length of the diameter of the circle.

Using the distance formula,

[tex]\Rightarrow d=\sqrt{(x_2-x_1)^2+(y_2-y_2)^2} \\\\\Rightarrow d=\sqrt{(7-5)^2+(6-8)^2} \\\\\Rightarrow d=\sqrt{2^2+(-2)^2}\\\\\Rightarrow d=\sqrt{4+4}\\\\\Rightarrow d=2\sqrt{2}~units[/tex]

We know that the diameter = 2 × radius

⇒ radius (r) = [tex]\frac{2\sqrt{2} }{2}[/tex]

⇒ r = [tex]\sqrt{2}[/tex] units

We know that the midpoint of the diameter is the center of the circle.

Using midpoint formula the center of the circle would be,

[tex]\Rightarrow O=(\frac{x_1+x_2}{2} ,\frac{y_1+y_2}{2} )\\\\\Rightarrow O=(\frac{5+7}{2} ,\frac{8+6}{2} )\\\\\Rightarrow O=(\frac{12}{2} ,\frac{14}{2} )\\\\\Rightarrow O=(6,7)[/tex]

Therefore, the center of the circle is (6,7)

Hence, the center of a circle = (6, 7)

the radius of a circle = [tex]\sqrt{2}[/tex]

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A superhero can fly from New York to Los Angeles in 30 minutes. The distance from New York to Los Angeles is approximately 2,450 miles.

How many miles per hour is the superhero flying?

Answers

Answer:  4900 mph

Work Shown:

30 min = 30/60 = 0.5 hours

distance = rate*time

rate = distance/time

rate = (2450 miles)/(0.5 hours)

rate = (2450/0.5) mph

rate = 4900 mph

For the sake of comparison, a typical commercial passenger jet can reach max speeds of about 600 mph.

A semi-circle sits on top of a rectangle to form the figure below. Find its area and perimeter. Use 3.14 for .
4 in.
6 in.
O A = 38.13 square inches, P = 32.84 inches
O A = 80.52 square inches, P = 32.84 inches
O A = 38.13 square inches, P = 23.42 inches
O A = 80.52 square inches, P = 23.42 inches

Answers

9514 1404 393

Answer:

  (c)  A = 38.13 square inches; P = 23.42 inches

Step-by-step explanation:

The radius of the circle is half the diameter, so is 3 inches. This means the entire figure will fit in a rectangle 6 inches wide and 4+3 = 7 inches high. The perimeter of such a rectangle is ...

  P = 2(L+W) = 2(7+6) = 26 inches

The area of that rectangle is ...

  A = LW = (7)(6) = 42 square inches

Then area of the given figure is less than 42 square inches, and the perimeter is less than 26 inches. The only answer choice that matches these bounds is ...

  A = 38.13 square inches; P = 23.42 inches

please help !!!!
i would really appreciate it ​

Answers

Answer: A

Step-by-step explanation: x=-2, y=3, z=-3

Answer:

A. -2, 3, -3

Step-by-step explanation:

x = 7 - 2y + z

y = 21 + 6x + 2z = 21 + 6×(7 - 2y + z) + 2z =

= 21 + 42 - 12y + 6z + 2z = 63 - 12y + 8z

13y = 63 + 8z

y = (63 + 8z)/13

2x + 2y - 3z = 11

2×(7 - 2y + z) + 2×(63 + 8z)/13 - 3z = 11

2×(7 - 2×(63 + 8z)/13 + z) + 2×(63 + 8z)/13 - 3z = 11

14 - 4×(63 + 8z)/13 + 2z + 2×(63 + 8z)/13 - 3z = 11

-2×(63 + 8z)/13 - z = -3

-2×(63 + 8z) - 13z = -39

-126 - 16z - 13z = -39

-29z = 87

z = -3

y = (63 + 8×-3)/13 = (63 - 24)/13 = 39/13 = 3

x = 7 - 2×3 + -3 = 7 - 6 - 3 = -2

Write two ratios equivalent to 24 : 9.

Answers

Answer:

8:3

16:6

Step-by-step explanation:

First, let's check if 9 and 24 have any common factor. If they do have any common ones, we must find the GCF (greatest common factor).

Factors of 9: 1, 3, 9

Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

The common factors both of the numbers share and 1 and 3. To find the GCF, simply compare one of the factors to the other.

1 < 3

Now that we know the GCF, we can divide the two numbers in the ratio 24 : 9 by it (3).

24:9

24/3:9/3

8:3

Now that our ratio is simplified, it's going to be much easier to find more ratios that are equivalent. 8:3 is already one equivalent ratio, but if we multiply each number in the ratio by any other number, we can get a new equivalent ratio. Let's multiply each number in the ratio by 2:

8:3

8 ⋅ 2:3 ⋅ 2

16:6

So, another equivalent ratio to 24:9 (and 8:3) is 16:6.

Please help explanation need it

Answers

Step-by-step explanation:

jejejebe. s shs sjs sibskkw

Làm ơm giúp tôi giải bài tập kinh tế vi mô này với

Answers

Step-by-step explanation:

i don't know this language

I need help please
Don’t skip the questions if you know the answer please I need the answers as soon as possible!!

Answers

y=x²-10x-7

a>0 so we will be looking for minimum

x=-b/2a=10/2=5

y=25-50-7=-32

Answer: (5;32)

y=-4x²-8x+1

а<0 so we will be looking for maximum

х=-b/2a=8/-8=-1

у=4+8+1=13

Maximum point (-1;13)

A number increased by a% and decreased by 80% is 400. What is the number?

Answers

Answer:

[tex]x = \frac{2000 }{(\frac{a+100}{100})}[/tex]

updated response , given that you confirmed the question....

if the percent is the variable a% then ....

[tex]x*(\frac{a+100}{100}) = 2000[/tex]

[tex]x = \frac{2000 }{(\frac{a+100}{100})}[/tex]

I think that there is missing information here ....

you can make any number work here the result of the number being increased by the percent has to be 2000...

so if if the number is 1000 then the percent would be 100%

if you make the number  1500 then the percent would be 33 1/3 %

Step-by-step explanation:

The number is [tex]\frac{2000}{(1+\frac{a}{100})}[/tex]

What will be the new number when the original number is increased by a% and decreased by 80%?

Let us assume that the number be x.

When the number x is increased by  a% the new number will be,

[tex]x(1+\frac{a}{100})[/tex]

Now, this number is decreased by 80%. So, the new number will be,

[tex]x(1+\frac{a}{100})*(1-\frac{80}{100} )\\=x(1+\frac{a}{100})*(1-0.8 )\\=x(1+\frac{a}{100})*0.20[/tex]

By the given condition,

When x increased by a% and decreased by 80% it becomes 400

Therefore, we can write

[tex]x(1+\frac{a}{100})*0.20=400[/tex]

[tex]x(1+\frac{a}{100})=\frac{400}{0.20}[/tex]

[tex]x(1+\frac{a}{100})=2000[/tex]

[tex]x=\frac{2000}{(1+\frac{a}{100})}[/tex]

So, the number will be [tex]\frac{2000}{(1+\frac{a}{100})}[/tex].

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find the missing segment below brainly

Answers

Let missing side be x

Using basic proportionality theorem

[tex]\\ \sf\longmapsto \dfrac{6}{4}=\dfrac{x}{20-x}[/tex]

[tex]\\ \sf\longmapsto 6(20-x)=4x[/tex]

[tex]\\ \sf\longmapsto 120-6x=4x[/tex]

[tex]\\ \sf\longmapsto 120=6x+4x[/tex]

[tex]\\ \sf\longmapsto 120=10x[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{120}{10}[/tex]

[tex]\\ \sf\longmapsto x=20[/tex]

The lengths of pregnancies in a small rural village are normally distributed with a mean of 264.1 days and a standard deviation of 12.9 days. In what range would you expect to find the middle 95% of most pregnancies

Answers

Answer:

The range of the 95% data (X) =  238.3 days <  X < 289.9 days

Step-by-step explanation:

Given;

mean of the normal distribution, m = 264.1 days

standard deviation, d = 12.9 days

between two standard deviation below and above the mean is 96% of all the data.

two standard deviation below the mean = m - 2d

                                                                   = 264.1 - 2(12.9)

                                                                   = 238.3 days

two standard deviation above the mean = m + 2d

                                                                    = 264.1 + 2(12.9)

                                                                     = 289.9 days

The middle of the 95% of most pregnancies would be found in the following range;

238.3 days <  X < 289.9 days

Explain how to multiply
the following
binomials
(2x - y)(2x + y).

Answers

Step-by-step explanation:

you can just use the punnet square method to multiply it

Use FOIL; first, outer, inner, last. Multiply the first terms in each binomial, the outer terms of each binomial, the inner terms of each binomial, and the last terms of each binomial. In this case, you multiply 2x*2x, 2x*y, -y*2x, and -y*y.

Help please:)) 2. When shipping ice cream, melting is understandably a big concern. You will notice that ice cream is not generally packaged in a cube-shaped container. A standard container of ice cream contains 1 L, or 1000 cm3 of ice cream,

a. What would be the optimal dimensions (radius and height) to minimize surface area?

b. What would the surface area be?

C. Suggest at least two reasons why this is different from the ice cream packaging that you see in the stores.​

Answers

Answer:

a. The radius r = 5.42 cm and the height h = 10.84 cm

b. 553.73 cm²

c. i. Beauty ii. Design

Step-by-step explanation:

a. What would be the optimal dimensions (radius and height) to minimize surface area?

The volume of the standard container is a cylinder and its volume is V = πr²h where r = radius of container and h = height of container.

Since V = 1000 cm³,

1000 cm³ = πr²h  (1)

Now, the surface area of a cylinder is A = 2πr² + 2πrh where r and h are the radius and height of the cylinder.

From (1), h = 1000/πr².

Substituting h into A, we have

A = 2πr² + 2πrh

A = 2πr² + 2πr(1000/πr²)

A = 2πr² + 2000/r

To maximize A, we differentiate A with respect to r and equate to zero to find the value of r at which A is maximum.

So, dA/dr = d[2πr² + 2000/r]/dr

dA/dr = d[2πr²]/dr + d[2000/r]/dr

dA/dr = 4πr - 2000/r²

Equating the equation to zero, we have

4πr - 2000/r² = 0

4πr = 2000/r²

r³ = 2000/4π

r = ∛(1000/2π)

r = 10(1/∛(2π))

r = 10(1/∛(6.283))

r = 10/1.8453

r = 5.42 cm

To determine if this value of r gives a minimum for A, we differentiate dA/dr with respect to r.

So, d(dA/dr)/dr = d²A/dr²

= d[4πr - 2000/r²]/dr

= d[4πr]/dr - d[2000/r²]/dr

= 4π  + 4000/r³

Substituting r³ = 2000/4π into the equation, we have

d²A/dr² = 4π  + 4000/r³ = 4π  + 4000/(2000/4π) = 4π  + 2 × 4π = 4π + 8π = 12π > 0

Since d²A/dr² = 12π > 0, then r = 5.42 cm gives a minimum for A.

Since h = 1000/πr²

h = 1000/π(5.42)²

h = 1000/92.288

h = 10.84 cm

So, the radius r = 5.42 cm and the height h = 10.84 cm

b. What would the surface area be?

Since the surface area, A = 2πr² + 2πrh

Substituting the values of r and h into A, we have

A = 2πr² + 2πrh

A = 2πr(r + h)

A = 2π5.42(5.42 + 10.84)

A = 10.84π(16.26)

A = 176.2584π

A = 553.73 cm²

c. Suggest at least two reasons why this is different from the ice cream packaging that you see in the stores.​

i. Beauty

ii. Design

The total amount of spending per​ year, in​ billions, on pets in a certain country x years after 2000 is given by the following function. ​P(x)=2.1786+25.2 ​a) Determine the total amount of spending per year on pets in 2007 and in 2012. ​b) Find and explain what it represents.

Answers

Answer:

40.4502 billion dollars

51.3432 billion dollars

Step-by-step explanation:

Given :

Total amount spent in billions in pets x years after year, 2000 ;

P(x)=2.1786x + 25.2

Amount spent in 2007 ;

x = 2007 - 2000 = 7 years

Put x = 7 in the equation :

P(7)=2.1786(7) + 25.2 = 40.4502

Amount spent in 2012 :

x = 2012 - 2000 = 12 years

Put x = 12 in the equation :

P(12) = 2.1786(12) + 25.2 = 51.3432

The amount spent in billik dollars on pets in :

2007 = $404502 billion

2012 = $51.3432 billion

Which graph shows a set of ordered pairs that represent a function?

Answers

Answer:

Graph C.

*See attachment below

Step-by-step explanation:

A graph that shows a set of ordered pairs representing a function would have each x-value being plotted against only one y-value. That is, every x-value must have exactly one y-value. Every x-value must not have more than 1 y-value being plotted against it.

The graph that shows this is the graph in option as shown in the attachment below.

Which of the following statements are true?

Answers

Answer:

last one

Step-by-step explanation:

they both whole

Is (5, 4) a solution to the equation y = x − 1?

yes or no

Answers

Yes 5,4 is y=x-1 actually anything can be those symbols as long as they add up to the Equation
Yes it is a solution to that equation

Use the drop-down menu to create true statements,
If the graph of an inverse passes the
, you know that the inverse is
a function,
The composition of a function and its inverse is
always
DONE
DOWE
The range values of an inverse are the
values of the original function,
The graph of an inverse is the reflection of the
graph of the function over the line
DONE
DOWE

Answers

Answer:

A) Vertical test

B) y=x

C) x

D) domain

If the graph of an inverse passes the Vertical Line Test, you know that the inverse is a function.

What is Inverse Function?

Inverse functions are functions which can be reversed in to another function.

Then the function is said to be the inverse of the second function.

The test which is used to know whether an inverse is a function or not is Vertical line Test.

So, if the graph of an inverse passes the Vertical Line Test, you know that the inverse is a function.

Composition of a function and it's inverse is always x.

Let y = f(x) be a function. Then x = f⁻¹ (y)

(f⁻¹of)(x) = f⁻¹ (f(x)) = f⁻¹ (y) = x

The graph of an inverse is the reflection of the graph of the function over the line y = x.

The range values of the inverse function are the domain values of the original function.

Hence the blank terms are found.

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sold 72 books. if ratio of books to bookmarks is 9:2, how many bookmark was sold?

Answers

Answer:

16 bookmarks were sold

Answer:

40

Step-by-step explanation:

They sold 9 book marks for every 2 books (9:2 ratio).

72/9 = 2/x

Cross multiply. 72 * x = 72x

9 * 2 = 18

72 divided by 18 = 40

On January 2, 2008, the American Idol website (www .americanidol) conducted an online poll that asked respondents which contestant they liked best among six former contestants. To become part of the sample, respondents simply clicked on a response. Of the 941,434 responses to this poll, 55% voted for Clay Aiken. We can conclude that _________________________________ .
a. the sample is too small.
b. a fraction of the millions of people who watched the TV show to draw any conclusion.
c. most Americans prefer Clay Aiken out of those former contestants.
d. the poll uses voluntary response, so the results tell us little about the population of all adults.

Answers

Answer:

Online Poll

We can conclude that

c. most Americans prefer Clay Aiken out of those former contestants.

Step-by-step explanation:

Sample responses received from the poll = 941,434

Proportion of voters for Clay Aiken = 55%

Computed proportion of voters for the other 5 contestants = 45% (100% - 55%)

This gives an average of 7.5% (45%/5) for the other 5 contestants.

Therefore, the conclusion is that "most Americans prefer Clay Aiken out of those former contestants" in the American Idol contest.

Let f(x) = e ^3x/5x − 2. Find f'(0).

Answers

Answer:

Step-by-step explanation:

Our friend asking what the actual function is has a point. I completed this under the assumption that what we have is:

[tex]f(x)=\frac{e^{3x}}{5x-2}[/tex] and used the quotient rule to find the derivative, as follows:

[tex]f'(x)=\frac{e^{3x}(5)-[(5x-2)(3e^{3x})]}{(5x-2)^2}[/tex] and simplifying a bit:

[tex]f'(x)=\frac{5e^{3x}-[15xe^{3x}-6e^{3x}]}{(5x-2)^2}[/tex]and a bit more to:

[tex]f'(x)=\frac{5e^{3x}-15xe^{3x}+6e^{3x}}{(5x-2)^2}[/tex] and combining like terms:

[tex]f'(x)=\frac{11e^{3x}-15xe^{3x}}{(5x-2)^2}[/tex] and factor out the GFC in the numerator to get:

[tex]f'(x)=\frac{e^{3x}(11-15x)}{(5x-2)^2}[/tex]  That's the derivative simplified. If we want f'(0), we sub in 0's for the x's in there and get the value of the derivative at x = 0:

[tex]f'(0)=\frac{e^0(11-15(0))}{(5(0)-2)^2}[/tex] which simplifies to

[tex]f'(0)=\frac{11}{4}[/tex] which translates to

The slope of the function is 11/4 at the point (0, -1/2)

Phân loại theo kiểu bố trí (cấu trúc) của mẫu sổ kế toán không gồm sổ nào trong các sổ dưới đây

Answers

Answer:

I I want everything in English

Step-by-step explanation:

it is difficult to read other languages write it in English please

please help, will give brainliest!!!!

Answers

Answer:

3

Step-by-step explanation:

3 - 3/x

----------------

1 - 1/x

Multiply the top and bottom by x

x(3 - 3/x)

----------------

x(1 - 1/x)

3x -3

------------

x-1

Factor the numerator

3(x-1)

-------

x-1

Cancel like terms

3

-----

1

3

There are 16 more people in front of Kollam on a line than behind him. There are five times as many people in front of him as behind him. How many people are on the line?

Answers

Answer:

There are 21 people in the line (including Kollam himself).

Write the equation of the line in fully simplified slope-intercept form.

Answers

y=-5x +8

y=mx+b

The slope is rise over run, you can use the points on there to determine detla y/ delta x. Then the b is the y intercepts, which is where the function passes the y axis.
y=-5x+8 is the correct answer

Which expression is equivalent to 5y^-3?​

Answers

Answer:

5/y^3

Step-by-step explanation:

which expression is equivalent to 5y^-3

for example a^-1 = 1/a

5y^-3 = 5/y^3

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