Determine if f(x, y) = 10 − x^2 − y^2
is increasing or decreasing at (7, −3) if we
take y to be constant and let x vary. Also determine if f(x, y) is increasing at
(7, −3) if we take x to be constant and let y vary.

Answer:

Ann has $30

Ryan has $63

Keith has $21

Step-by-step explanation:

First I assigned variables to the amounts each owns. It doesn't really matter what letters, but I said x represents Ann's money, y represents Ryan's money, and z represents Keith's money.

We know that with all their money added up, they have 114. This gives us our first equation;

114=x+y+z

Ryan has 3 times what Keith has, which, in terms of variables, is

y=3z

Keith has nine dollars less than Ann. Less, in word problems, always means subtraction. This gives us our third equation:

z=x-9

Okay so the impulse is to put z=x-9 and y=3z into the first equation, but the goal is to create an equation with only one variable so this will not work.

What we do instead is sub z=x-9 into y=3z. This gives

y=3(x-9)=3x-27

Now that both y and z are in terms of x, we plug those equations into the first and then solve for x;

114=x+3x-27+x-9

114=5x-36

150=5x

30=x

Now that we know x, we can find z and y using the equations from earlier:

z=30-9=21

y=3(21)=63

x=30, y=63, and z=21, thus Ann has $30, Ryan has $63, and Keith has $21.

Hi,

AxB = 0 means A=0. or B=0

so 2 solutions :

4x-3= 0

4x=3

x = 3/4

and x+2 = 0.

x= -2

solutions are : -2 +and 3/4

2 answers

1) -2

2) -3/4

that's what I got, you can confirm if it's correct or not... I'm not sure

have a nice dayʘ‿ʘ

9514 1404 393

Answer:

  Amy: $620

  Tom: $400

Step-by-step explanation:

The pay for 40 hours (1 week) is 40 times the pay for 1 hour:

  Amy: 40 × $15.50 = $620 . . . . Amy's pay for 1 week

  Tom: 40 × $10.00 = $400 . . . . Tom's pay for 1 week

Answer:

14 nickels

Step-by-step explanation:

One nickel is worth 5 cents, so find the value of 14 nickels by multiplying 14 by 5:

14(5)

= 70

So, 14 nickels is equal to the 70 cents that she has in her purse.

The correct answer is 14 nickels.

Answer:

10x-2x-4=8x-4 اتمنى لك التوفيق

Answer:

3y=x+5

Step-by-step explanation:

The slope of the line is (1/3). The equation of the line is y=(1/3)x+5/3 or 3y=x+5

Step-by-step explanation:

A manufacturer of computer memory chips produces chips in lots of 1000. If nothing has gone wrong in the manufacturing process, at most 7 chips each lot would be defective, but if something does go wrong, there could be far more defective chips. If something goes wrong with a given lot, they discard the entire lot. It would be prohibitively expensive to test every chip in every lot, so they want to make the decision of whether or not to discard a given lot on the basis of the number of defective chips in a simple random sample. They decide they can afford to test 100 chips from each lot. You are hired as their statistician.

There is a tradeoff between the cost of eroneously discarding a good lot, and the cost of warranty claims if a bad lot is sold. The next few problems refer to this scenario.

Problem 8. (Continues previous problem.) A type I error occurs if (Q12)

Problem 9. (Continues previous problem.) A type II error occurs if (Q13)

Problem 10. (Continues previous problem.) Under the null hypothesis, the number of defective chips in a simple random sample of size 100 has a (Q14) distribution, with parameters (Q15)

Problem 11. (Continues previous problem.) To have a chance of at most 2% of discarding a lot given that the lot is good, the test should reject if the number of defectives in the sample of size 100 is greater than or equal to (Q16)

Problem 12. (Continues previous problem.) In that case, the chance of rejecting the lot if it really has 50 defective chips is (Q17)

Problem 13. (Continues previous problem.) In the long run, the fraction of lots with 7 defectives that will get discarded erroneously by this test is (Q18)

Problem 14. (Continues previous problem.) The smallest number of defectives in the lot for which this test has at least a 98% chance of correctly detecting that the lot was bad is (Q19)

(Continues previous problem.) Suppose that whether or not a lot is good is random, that the long-run fraction of lots that are good is 95%, and that whether each lot is good is independent of whether any other lot or lots are good. Assume that the sample drawn from a lot is independent of whether the lot is good or bad. To simplify the problem even more, assume that good lots contain exactly 7 defective chips, and that bad lots contain exactly 50 defective chips.

Problem 15. (Continues previous problem.) The number of lots the manufacturer has to produce to get one good lot that is not rejected by the test has a (Q20) distribution, with parameters (Q21)

Problem 16. (Continues previous problem.) The expected number of lots the manufacturer must make to get one good lot that is not rejected by the test is (Q22)

Problem 17. (Continues previous problem.) With this test and this mix of good and bad lots, among the lots that pass the test, the long-run fraction of lots that are actually bad is (Q23)

Answer:

loses  14 cents

- $0.14

Step-by-step explanation:

90%  $0.30   $(0.30)  $(0.27)

9%  $1.00   $0.40   $0.04  

1%  $10.00   $9.40   $0.09  

   $(0.14)

Let on of the angle be x

ATQ

97 + x = 180

x = 180 - 97 (Angles on same line adds upto 180°) (Linear pair cuz 2 angles)

x = 83

The unknown angle is 83°

Must click thanks and mark brainliest

if you are trying to work out -3/4 - (-1/4 - 1/2) then the answer is 0

I assume A ∆ B denotes the symmetric difference of A and B, i.e.

A ∆ B = (B - A) U (A - B)

where - denotes the set difference or relative complement, e.g.

B - A = {b ∈ B : b ∉ A}

It can be established that

A ∆ B = (A U B) - (A ∩ B)

so that

n(A ∆ B) = n(A U B) - n(A ∩ B) = 10 - 3 = 7

Not sure what you mean by p(A ∆ B), though... Probability?

Answer:

$480

Step-by-step explanation:

Let original price be x

{Original price - discount amount = sale price}

So, x - (x * 35/100) = 312

x - 35x/100 = 312

100x - 35x / 100 = 312

65x/100 = 312

65x = 31200

x = 31200/65

x = $480

So I think the original price of desk was $480

The original price of the desk is $480.

A discount is the reduction of either the monetary amount or a percentage of the normal selling price of a product or service.

Given that, a desk is being sold for $312.

Let the original price of the desk be x.

Here, x-35% of x =312

x- 35/100 ×x=312

x-0.35x=312

0.65x=312

x=312/0.65

x=480

Therefore, the original price of the desk is $480.

To learn more about the discount visit:

https://brainly.com/question/3541148.

#SPJ2

Answer:

?

How did you simplify

Answer:

Drawing 4 - 1/10

Drawing odd number - 1/2

Not drawing 3- 9/10

Drawing 5 or 6 -  1/5

Drawing a number greater than 9 - 0

Let me know if this helps!

Answer:

10.9

Step-by-step explanation:

[tex]a^2+b^2=c^2[/tex]

[tex]9.1^2+6^2=c^2[/tex]

[tex]82.81+36=c^2[/tex]

[tex]c^2=118.81[/tex]

[tex]c=\sqrt{118.81} =10.9[/tex]

9514 1404 393

Answer:

  17

Step-by-step explanation:

The points at the ends of the interval are ...

  (0, f(0)) = (0, 0)

  (7, f(7)) = (7, 119)

The average rate of change is given by the slope formula:

  m = (y2 -y1)/(x2 -x1)

  m = (119 -0)/(7 -0) = 119/7 = 17

Answer:

Rs. 11132

Step-by-step explanation:

formula for depriciation= P(1-R/100)^T

p= principal, r=rate, t=time

Answer:

15162

Step-by-step explanation:

after 1 year= 16800*95%= 15960

after 2 year= 15960*95%= 15162

Answer:

option A

Step-by-step explanation:

wx and zy making 90 angle with each other therefore they are perpendicular.

wx and ab making 0 angle with each other therefore they are parallel

-4 ≤ x ≤ 6

x ≥ -4

3x ≥ -12

3x + 12 ≥ 0

3x + 14 ≥ 2

6 ≥ x

6 - x ≥ 0

1 - x ≥ -5

A. 3x + 14 ≥ 2 and 1 - x ≥ -5

Answer:

8 =x

Step-by-step explanation:

- 18 = -3x + 6

Subtract 6 from each side

-18-6 = -3x+6-6

-24 = -3x

Divide each side by -3

-24/-3 = -3x/-3

8 =x

Answer:

x= 8

Step-by-step explanation:

[tex]\sf{}[/tex]

=> -3x+6 = -18

=> -3x+6-6= -8-6

=> -3x= -24

=> x= 8

Leontief input output model (technology matrix) is an economic model that shows the quantitative relationship and sectorial interdependency in a national economy

The responses with  regards to the question are;

(i) The technology matrix for the economy is presented as follows;

[tex]\mathbf{ A} =\left[\begin{array}{ccc}Agric&&Textile\\0.4&&0.1\\&&\\0.1&&0.2\end{array}\right] \begin{array}{ccc}\mathbf{Per \ Unit}\\Agriculture\\\\Textile\end{array}\right][/tex]

(ii) The required gross production of each industry to meet the desired surplus are;

50 units of agriculture and 250 units of textile

The reason the above values are correct is as follows:

(i) The given parameters are;

The industries in the economy = Agricultural industry and textile industry

Units of agricultural input required per unit of agricultural output = 0.4

Units of textile input required per unit of agricultural output = 0.1

Units of agricultural input required per unit of textile output = 0.1

Units of textile input required per unit of textile output = 0.2

Let X represent agriculture, and let Y represent textile, we have;

[tex]Agric \ for \ agric = \dfrac{0.4 \ units \ of \ agriculture}{1\ unit \ of \ agric \ produced} \times X \ Agric \ produced= 0.4 \cdot X[/tex]

[tex]Agric \ for \ textile = \dfrac{0.1 \ units \ of \ agriculture}{1\ unit \ of \ textile \ produced} \times Y \ textile \ produced= 0.1 \cdot Y[/tex]

We also have;

Textile for agriculture = 0.1·X

Textile for textile = 0.2·Y

Therefore;

X = 0.4·X + 0.1·Y

Y = 0.1·X + 0.2·Y

Therefore;

The technology matrix for the economy is presented as follows;

[tex]\mathbf{Technology \ matrix, A} =\left[\begin{array}{ccc}Agric&&Textile\\0.4&&0.1\\&&\\0.1&&0.2\end{array}\right] \begin{array}{ccc}\mathbf{Per \ Unit}\\Agriculture\\\\Textile\end{array}\right][/tex]

(ii)  Let P represent the production vector, and let d represent the demand vector, we have;

[tex]P = \left[\begin{array}{c}X \\Y\end{array}\right][/tex], [tex]d = \left[\begin{array}{c}5 \\195\end{array}\right][/tex]

P = A·P + d

∴ P - A·P = d

Therefore;

[tex]P = \mathbf{ \dfrac{d}{(I - A)}}[/tex]

Where I = The 2 by 2 identity matrix

We get;

[tex]I - A =\left[\begin{array}{ccc}1&&0\\&&\\0&&1\end{array}\right] - \left[\begin{array}{ccc}0.4&&0.1\\&&\\0.1&&0.2\end{array}\right] = \mathbf{\left[\begin{array}{ccc}0.6&&-0.1\\&&\\-0.1&&0.8\end{array}\right]}[/tex]

With the use of a graphing calculator, we have;

[tex]P =\left[\begin{array}{c}X \\Y\end{array}\right] = \dfrac{\left[\begin{array}{c}5 \\195\end{array}\right]}{\left[\begin{array}{ccc}0.6&&-0.1\\&&\\-0.1&&0.8\end{array}\right]} = \left[\begin{array}{ccc}50\\\\\ 250\end{array}\right][/tex]

The required gross product of agriculture, X = 50 units

The required gross product of textile, Y = 250 units

Learn more about the Leontief input output model here:

https://brainly.com/question/15417573

We have that he technology matrix for this economy and the  the gross production of each industry are

a)    [tex]X= \begin{vmatrix}0.4 & 0.1 \\0.1 & 0.2\end{vmatrix}[/tex]

b)    [tex]\begin{vmatrix}A\\T\end{vmatrix}=\begin{vmatrix}50\\250\end{vmatrix}[/tex]          

From the Question we have told that

Each unit of agricultural output requires 0.4 unit of agricultural input

Each unit of agricultural output requires 0.1 unit of textiles input.

Each unit of textiles output requires 0.1 unit of agricultural input

Each unit of textiles output requires 0.2 unit of textiles input.

Generally the technology matrix for this economy is given below

With

X =Agricultural industry Gross output

Y= Textile industry Gross Output

Therefore

[tex]X= \begin{vmatrix}0.4 & 0.1 \\0.1 & 0.2\end{vmatrix}[/tex]

b)

From the Question we are told that

Surpluses of 5 units of agricultural products and 195 units of textiles are desired.

Therefore, we have Desired surplus matrix of

[tex]D= \begin{vmatrix}5\\195\end{vmatrix}[/tex]

Generally the Technology equation is mathematically given as

[tex](I-X)\phi=D[/tex]

Where

X =Agricultural industry Gross output

I=A Unit matrix

\phi=Matrix of gross production

Therefore

[tex]\begin{vmatrix}1 & 0\\0 & 1\end{vmatrix}-(\begin{vmatrix}0.4 & 0.1 \\0.1 & 0.2\end{vmatrix}))\begin{vmatrix}A\\T\end{vmatrix}=\begin{vmatrix}5\\195\end{vmatrix}[/tex]

[tex]\begin{vmatrix}A\\T\end{vmatrix}=\begin{vmatrix}50\\250\end{vmatrix}[/tex]

In conclusion

The technology matrix for this economy and the  the gross production of each industry are

[tex]X= \begin{vmatrix}0.4 & 0.1 \\0.1 & 0.2\end{vmatrix}[/tex]

[tex]\begin{vmatrix}A\\T\end{vmatrix}=\begin{vmatrix}50\\250\end{vmatrix}[/tex]         Respectively

In conclusion

https://brainly.com/question/16863924

5

Answer:

1050

Step-by-step explanation:

Natural Numbers are positive whole numbers. They aren't negative, decimals, fractions. We can just divide 5 into 100 to find how many natural numbers go up to 100 and just add them but that is just to much.

There is a easier method.

E.g: Natural Numbers that are divisible by a Nth Number. is the same as adding the Nth Numbers to a multiple of that Nth Term. For example, let say we need to find numbers divisible by 2. We know that 4 is divisible by 2 because 4/2=2. We can add the Nth numbers which is 2 to 4. 4+2=6. And 6 is divisible by 2 because 6/2=3. We can call this a arithmetic series. A series which has a pattern of adding a common difference

Back to the problem, we can use the sum of arithmetic series formula,

[tex]y = x( \frac{z {}^{1} + {z}^{n} }{2} )[/tex]

Where x is the number of terms in our sequence. Z1 is the fist term of our series. ZN is our last term. And y is the sum of all of the terms

The first term is 5, the numbers of terms being added is 20 because 100/5=20. The last term is 100.

[tex]y = 20( \frac{5 + 100}{2} )[/tex]

[tex]y = 20( \frac{105}{2} )[/tex]

[tex]y = 1050[/tex]

Answer:

Step-by-step explanation:

Answer:

sec^2(x)

Tell me if I'm correct or wrong. If I'm correct, plz mark me brainliest!

Step-by-step explanation:

Recall that

[tex]\sin (\frac{\pi}{2} - x) = \cos x[/tex]

[tex]\cos (\frac{\pi}{2} - x) = \sin x[/tex]

So we can rewrite the given expression as

[tex]\dfrac{\cos^2 x}{\sin^2 x} + (\sin^2 x + \cos^2 x)[/tex]

[tex]\Rightarrow \dfrac{\cos^2 x}{\sin^2 x} + 1[/tex]

or

[tex]\dfrac{\cos^2 x + \sin^2 x}{\sin^2 x} = \dfrac{1}{\sin^2 x} = \csc^2 x[/tex]

Answer:

4.2 mi²

Step-by-step explanation:

Volume of a cone = (1/3)πr²h, where r = radius and h = height

(1/3)πr²h

= (1/3)×π×1²×4

= 4π/3

= 4.2 mi² (rounded to the nearest tenth)

Answer:

6 pies

Step-by-step explanation:

For 60 - 89 cherries there are 10 pies

For 90 -119 cherries there are 4 pies

10 -4 = 6

There are 6 more pies in the 60 -89 cherries category than in the 90-119 category

Question: -4 + 5x -7 = 10 + 3x -2x

⇒ 5x -11 = 10 + x

⇒ 5x - x = 10+11

⇒ 4x = 21

⇒ x = 21/4

Answer is Option D

x = 21/4

Must click thanks and mark brainliest

Answer:

2.592 x 10^5

Step-by-step explanation:

1st step: Calculate for 1 day.

if 1 hour = 3.6 X 10³

24 hrs = (3.6 x 10³) X (2.4 x 10¹)

= 3.6 x 2.4 X 10⁴

= 8.64 x 10⁴

2nd Step: Calculate for 3 days;

if 1 day = 8.64 x 10⁴

3 days = (8.64 x 10⁴) X (0.3 x 10¹)

= 8.64 x 0.3 x 10^5

= 2.592 x 10^5