Which matrix equation represents the system of equations?

Answers

Answer 1

Answer:

B. [tex]\left[\begin{array}{ccc}-1&2\\0&1\\\end{array}\right] \left[\begin{array}{ccc}x\\y\\\end{array}\right] =\left[\begin{array}{ccc}0\\-2\\\end{array}\right][/tex]

Step-by-step explanation:

Given the systems of equations

-x + 2y = 0

y = -2

This can also be written as:

-x + 2y = 0

0x + y = -2

We are to write in this form AX = b

A is a 2by2 matrix with coefficients of x nd y

X is a column matrix containing the unknown

b is a column matrix with the values at the right hand sides (0 and -2)

Writing in matrix form;

[tex]\left[\begin{array}{ccc}-1&2\\0&1\\\end{array}\right] \left[\begin{array}{ccc}x\\y\\\end{array}\right] =\left[\begin{array}{ccc}0\\-2\\\end{array}\right][/tex]


Related Questions

Please help out really need it !!

Answers

Answer:

use the area formula

Step-by-step explanation:

Answer:

rounded to the nearest tenth i think its 40

How many of 320 million Americans would you predict wear contact lens

Answers

Answer:

I think 40 - 60 Million Americans would wear contact lenses.

Find the measure of the missing angles in the regular polygon below.

Answers

Step-by-step explanation:

First, we can see that the angles inside the polygon form a full circle, as it goes fully around. Therefore, the sum of the angles around the center of the circle (such as m < 7) is 360 degrees. Since it is a regular polygon, and the lines are going from the center to its corners, the 6 angles directly surrounding the center are equal.

Each angle is therefore 360/6 = 60 degrees, so m<7 is 60 degrees.

For m<8, we can see that a line bisects one of the 6 angles surrounding the center. Therefore, m<8 is 1/2 of the angle it bisects, which is equal to 360/6 = 60 degrees, and m<8 = 60/2 = 30 degrees

Finally, we can see that there are 6 sides of the polygon. For a polygon with n number of sides, the sum of its interior angles is equal to (n-2) * 180. Here, there are 6 sides, so the sum of this polygon's interior angles is (6-2) * 180 = 4 * 180 = 720. Because this is a regular polygon, each interior angle is the same, and because there are 6 of them, each one is 720/6 = 120 degrees. As shown in the picture, m < 9 is seemingly one-half of an interior angle, as it is bisected by a line from the center to a corner.

Therefore, m <9  = 120 /2 = 60 degrees

In terms of the perimeter of a regular polygon, the area of a regular polygon is given as, Area = (Perimeter × apothem)/2, in which perimeter = number of sides × length of one side.

given f(x)=2x-4 and g(x)=x213, determine gf[x]]​

Answers

Step-by-step explanation:

you have to substitute the function g(x) where there's x in the function f(x)

gf(x)=2(x213)-4

if that's x two thirteen then you can multiply the 2 outside the brackets by it

giving you a final answer of

gf(x)=426x-4

hope it helps and sorry if am wrong

Salma invested $8000 in a fund for 6 years and was paid simple interest. The total interest that she received on the investment was $1400. As a percentage, what was the annual interest rate of her investment?

Answers

9514 1404 393

Answer:

  about 2.917%

Step-by-step explanation:

The simple interest formula can be used. Fill in the known values and solve for the unknown.

  I = Prt . . . . principal P invested at rate r for t years

  1400 = 8000(r)(6)

  r = 1400/48000 = 7/240 = 0.0291666...

Salma's interest rate was about 2.917% per year.

three cards are drawn from an ordinary desk and not replaced
find probability a.getting 3 jackets​
​​​

Answers

Answer:

Assuming you meant three jacks:

1 in 5525 or else 1/5525.

Step-by-step explanation:

You start with a full deck of 52 and 4 jacks. After each draw, you reduce both the jacks and total deck by one. Your first draw would be 4/52. The next would be 3/51. The final draw would be 2/50. You multiply each fraction together as you need all of them to happen, and that is your odds of drawing 3 jacks in a row without replacement.

Suppose you deposit $500 in a savings account where the interest earned is compounded
continuously at a rate of 10%. How many years will it take the balance in the account to reach
$8000 (round your answer to the nearest year)?

Answers

14 years after rounding to the nearest year

The number of bacteria in a colony increases by 10% every 2 hours. What is the overall percent increase after 4 hours?

Answers

The number of bacteria in a culture is increasing according to the law of exponential growth. There are 125 bacteria in the culture after 2 hours and 350 bacteria after 4 hours.

The overall percent increase after 4 hours is 21% if the number of bacteria in a colony increases by 10% every 2 hours option (G) is correct.

What is the percentage?

It's the ratio of two integers stated as a fraction of a hundred parts. It is a metric for comparing two sets of data, and it is expressed as a percentage using the percent symbol.

We have:

The number of bacteria in a colony increases by 10% every 2 hours.

Let there be 100 bacteria in the starting

In the first 2 hours :

= (100×10%) + 100

= 10 + 100

= 110

Again after 2 hours:

= (110×10%) + 110

= 11 + 110

= 121

= (121 - 100)

= 21

Thus, the overall percent increase after 4 hours is 21% if the number of bacteria in a colony increases by 10% every 2 hours option (G) is correct.

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what are all the solutions (in exact values) to tan x = 1/4 [-π,π] ?

Answers

9514 1404 393

Answer:

arctan(1/4)arctan(1/4) -π

Step-by-step explanation:

The inverse tangent of 1/4 is an irrational number, only expressible exactly as ...

  arctan(1/4)

This is a first-quadrant angle. There is a matching third-quadrant angle with the same tangent:

  arctan(1/4) -π

Determine the area of the given parallelogram with length 11 and altitude five

Answers

9514 1404 393

Answer:

  55 square units

Step-by-step explanation:

The area of a parallelogram is the product of base length and height:

  A = bh

  A = (11)(5) = 55 . . . area of the given parallelogram in square units

Need help giving 10 Points. Answer—and explanation

Answers

I think it’s the 3rd one because 4x6=24, and these numbers can be multiplied into 24

Find the length of BC
A. 6.81
B. 7.64
C. 13.37
D. 29.44

Answers

Answer:

13.37 = BC

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

cos theta = opp / hyp

cos 27 = BC / 15

15 cos 27 = BC

13.36509 = BC

Rounding to the nearest hundredth

13.37 = BC

Find x please explanation need it

Answers

Cos 19 = Adjacent/hypotenuse
(Cos 19)(21) = 19.9

d) A product contains three lasers, and the product fails if any of the lasers fails. Assume the lasers fail independently. What should the mean life equal for 99% of the products to exceed 10000 hours before failure

Answers

Solution :

Let the probability laser works = p

The probability that the system works = [tex]$P(\text{all three component works}) = p^3 $[/tex]

                                                                                                                   = 0.99

Therefore, p = 0.9967

Now for the above probability critical z = -2.72

Hence, the mean life is equal to = [tex]10,000 + 2.72 \times 600[/tex]

                                                     = [tex]10,000+1632[/tex]

                                                     [tex]=11,632[/tex]

Simplify 9 + (-2)³

answer asap

Answers

Answer:

[tex]9+(-2)^{3} =9+[(-2)(-2)(-2)]=9+[4(-2)]=9+(-8)=9-8=1[/tex]

[tex]Hello[/tex] [tex]There![/tex]

[tex]AnimeVines[/tex] [tex]is[/tex] [tex]here![/tex]

This is quite simple, actually.

Here's a explanation.

[tex]9 + (-2)^{3}[/tex]

[tex]= 9 + - 8[/tex]

[tex]= 1[/tex]

[tex]HopeThisHelps!![/tex]

[tex]AnimeVines[/tex]

Rewrite the function f(x)=16^x in four different ways, using a different base in each case.

Answers

Answer:

X=1

f(x)=16^1

=16

X=2

f(x)=16^2

256

X=3

f(x)=16^3

=4096

X=4

f(x)=16^4

=65536

Here are four different ways to rewrite the function f(x) = 16^x, using a different base for each case:

Using base 2:

f(x) = (2^4)^x = 2^(4x)

Using base 3:

f(x) = (3^2)^x = 3^(2x)

Using base 10:

f(x) = (10^(log10(16)))^x = 10^(log10(16) * x)

Using base e (natural logarithm):

f(x) = (e^(ln(16)))^x = e^(ln(16) * x)

How to explain the function

In these rewritten forms, the exponentiation of the base is expressed as a simpler expression.

This involves the new base, which helps to illustrate the relationship between the original function and the different bases used.

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AVX Home Entertainment Inc recently began a "no-hassles" return policy. A sample of 505 customers who recently returned items showed 320 thought the policy was fair, 150 thought it took too long to complete the transaction, and the rest had no opinion. On the basis of this information, make an inference about customer reaction to the new policy. (Round your answers to 1 decimal place.)
Customer reaction Percent
Fair %
Too long %
No opinion %

Answers

Answer:

[tex]Fair = 63.4\%[/tex]

[tex]Too\ Long = 29.7\%[/tex]

[tex]No\ Opinion =6.9\%[/tex]

Step-by-step explanation:

Given

[tex]Total=505[/tex] --- customers

[tex]Fair = 320[/tex]

[tex]Too\ Long = 150[/tex]

Required

Complete the table

To complete the table, we simply divide each value by the total number of customers.

So, we have:

[tex]Fair = 320[/tex]

[tex]Fair = \frac{320}{505}[/tex]

[tex]Fair = 0.634[/tex]

Express as percentage

[tex]Fair = 0.634*100\%[/tex]

[tex]Fair = 63.4\%[/tex]

[tex]Too\ Long = 150[/tex]

[tex]Too\ Long = \frac{150}{505}[/tex]

[tex]Too\ Long = 0.297[/tex]

Express as percentage

[tex]Too\ Long = 0.297*100\%[/tex]

[tex]Too\ Long = 29.7\%[/tex]

For the last set, the percentage is calculated using:

[tex]No\ Opinion + Fair + Too\ Long = 100\%[/tex]

So, we have:

[tex]No\ Opinion + 63.4\% + 29.7\% = 100\%[/tex]

[tex]No\ Opinion + 93.1\% = 100\%[/tex]

Collect like terms

[tex]No\ Opinion =- 93.1\% + 100\%[/tex]

[tex]No\ Opinion =6.9\%[/tex]

Question 4 please provide explanation for question

Answers

Answer:

A

Step-by-step explanation:

We need to find a equation that is where the domain is all real numbers and the range is all real numbers greater than -3

A square root function cannot equal to all real numbers because we cant take the square root of a negative number. so B and C are already wrong.A cubic function range is all real numbers. so y can be greater than -3 but it would also include. values lesser than -3. so D is Wrong.

A is right, the domain of a absolute value function is all real numbers. The range of a absolute value is all numbers greater than or equal to zero but if we subtract 3, it changes into all real numbers greater than or equal to -3

An elevator is on the twelfth floor it goes down 11 floors and than up 5 floors what floor is the elevator on now

Answers

Answer:

The sixth floor

Step-by-step explanation:

the answer is that it's on the 5th floor now

Ann, Bob, Carol, and Denis own a candy store. After a large argument, they decide to dissolve their partnership using the sealed bid method. Ann bids $320,000 for the store, Bob bids $440,000 for it, Carol bids $240,000 for it, and Denis bids $400,000 for it.

Required:
a. What is Bob's fair share?
b. What is Carol's fair share?
c. What is Denis's fair share?

Answers

Answer:

Following are the solution to the given points:

Step-by-step explanation:

[tex]Ann=\$3,20,000\\\\Bob=\$4,40,000\\\\Carol=\$240,000\\\\Denis= \$4,00,000\\\\[/tex]

Each player's offer divided by the total number of players calculates the fair share

Ann's fair share [tex]= \frac{\$320,000}{4} = \$80,000\\\\[/tex]

Bob's fair share[tex]= \frac{\$440,000}{4} = \$110,000\\\\[/tex]

 Carol's fair share [tex]= \frac{\$240,000}{4} = \$60,000\\\\[/tex]

Denis's fair share [tex]= \frac{\$400,000}{4} = \$100,000\\\\[/tex]

 Because Bob has the highest bid, that receives in the business.

Payments:

 Ann [tex]\$80,000[/tex] paid by estate

 Bob [tex]= \$440,000 - \$110,000 = \$330,000[/tex] owes estate

 Carol [tex]= \$60,000[/tex] paid by estate

 Denis [tex]= \$100,000[/tex] paid by estate  

Surplus [tex]= \$330,000 - (\$80,000+\$60,000+ \$100,000) = \$90,000[/tex]  

Splitting the equally among the four players. therefore one of the each receives:

[tex]\frac{\$90,000}{4}= \$22,500[/tex]

The final settlement of the Ann receives:

[tex]= \$80,000+ \$22,500 = \$102,500[/tex]

Jeannine needs to decide what size to make a rectangular
garden in her yard. The dimensions must be natural numbers.
Jeannine wants the perimeter of her Chapter Reference
garden to be 50 dm. She wants the
width to be an even number of decimeters. How many
different combinations are possible? (Length is always longer than or equal to width.)

Answers

Answer:

Total number of possible combinations are 6

Length   width

23 dm     2m

21 dm       4 dm

19 dm       6 dm

17 dm         8 dm

15 dm         10 dm

13 dm          12 dm

Step-by-step explanation:

We are given that

Perimeter of rectangular garden=50 dm

Width is  even number.

Length is always longer than or equal to width.

Let length of rectangular garden=x

Width of  rectangular garden=y

We have to find the possible  number of combinations .

Perimeter of rectangular garden=[tex]2(x+y)[/tex]

[tex]2(x+y)=50[/tex]

[tex]x+y=50/2[/tex]

[tex]x+y=25[/tex]

If y=2 dm

x=25-2=23 dm

If y=4 dm

x=25-4=21 dm

If y=6 dm

x=25-6=19 dm

If y=8 dm

x=25-8=17 dm

If y=10 dm

x=25-10=15 dm

If y=12 dm

x=25-12=13 dm

If y=14 dm

x=25-14=11 dm

x<y

It is  not possible

Then, possible combinations are 6

Length   width

23 dm     2m

21 dm       4 dm

19 dm       6 dm

17 dm         8 dm

15 dm         10 dm

13 dm          12 dm

Which function has a range of y < 3?
y - 3(2)
y = 2(3)
O y=-(2)x+ 3
Oy- (2) * - 3

Answers

Given:

The range of a function is [tex]y<3[/tex].

To find:

The function for the given range from the given options.

Solution:

In option A, the given function is:

[tex]y=3(2)^x[/tex]

Here, [tex](2)^x[/tex] is always greater than 0. So, [tex]3(2)^x[/tex] is also greater than 0, i.e., [tex]y>0[/tex].

In option B, the given function is:

[tex]y=2(3)^x[/tex]

Here, [tex](3)^x[/tex] is always greater than 0. So, [tex]2(3)^x[/tex] is also greater than 0, i.e., [tex]y>0[/tex].

In option C, the given function is:

[tex]y=-(2)^x+3[/tex]

Here,

[tex](2)^x>0[/tex]

[tex]-(2)^x<0[/tex]

[tex]-(2)^x+3<0+3[/tex]

[tex]y<3[/tex]

The range of this function is [tex]y<3[/tex]. So, option C is correct.

In option D, the given function is:

[tex]y=(2)^x-3[/tex]

Here,

[tex](2)^x>0[/tex]

[tex](2)^x-3<0-3[/tex]

[tex]y<-3[/tex]

The range of this function is [tex]y<-3[/tex]

Therefore, the correct option is only C.

Listed below are the 35 members of the Metro Toledo Automobile Dealers Association. We would like to estimate the mean revenue from dealer service departments. The members are identified by numbering them 00 through 34. We want to select a random sample of five dealers. The random numbers are: 34, 32, 39, 94, 25, 71, 71, 13, 52, 39, 19, and 67. Which dealers would be included in the sample

Answers

Answer:

Following are the solution to the given question:

Step-by-step explanation:

There will be 35 members of the Toledo Automotive Metro from such reports

The Organization of Distributors. The membership is sequentially numbered between 00 and 34.

The five traders selected a random sample as follows:

[tex]34, 32, 39, 94, 25, 71, 71, 13, 52, 39, 19, 67[/tex]

The decision should be made in 00 and 34.

In this the remaining numbers 39, 94,. . . . .67 were not chosen because it is beyond the ranges that are 00-34.

The samples contain 34, 32, 25, 13, and 19 distributors.

when solving inequalities,name 2 steps that are the same as solving equations and one difference

Answers

9514 1404 393

Explanation:

same:

the addition property of equalitythe multiplication property of equality (for positive multipliers)

different:

the multiplication property of equality for negative multipliers

_____

Additional comment

Multiplication by a negative number has the effect of re-ordering numbers:

  -1 < 2 . . . 1 > -2 (both sides multiplied by -1)

Other functions can have the same effect, so care must be taken when applying functions to both sides of an inequality.

  1/2 > 1/3 . . . 2 < 3 (reciprocal function applied to both sides)

  30° < 60° . . . cos(30°) > cos(60°) (cosine function applied to both sides)

Find the area of a rectangle that measures 12ft by 3 1/3 ft

Answers

Answer:

40 ft^2

Step-by-step explanation:

The area of a rectangle is given by

A = l*w

   =12 * 3 1/3

Change to an improper fraction

   = 12 ( 3*3+1)/3

   = 12 (10/3)

     40

Answer:

[tex]40 {ft}^{2} [/tex]

Step-by-step explanation:

[tex]area = l \times b \\ = 12 \times 3 \frac{1}{3} \\ = 12 \times \frac{10}{3} \\ = \frac{120}{3} \\ = 40 {ft}^{2} [/tex]

Given $f(x) = \frac{\sqrt{2x-6}}{x-3}$, what is the smallest possible integer value for $x$ such that $f(x)$ has a real number value? please show steps. Thank you!

Answers

Given:

The function is:

[tex]f(x)=\dfrac{\sqrt{2x-6}}{x-3}[/tex]

To find:

The smallest possible integer value for $x$ such that $f(x)$ has a real number value.

Solution:

We have,

[tex]f(x)=\dfrac{\sqrt{2x-6}}{x-3}[/tex]

This function is defined if the radicand is greater than or equal to 0, i.e., [tex]2x-6\geq 0[/tex] and the denominator is non-zero, i.e., [tex]x-3\neq 0[/tex].

[tex]2x-6\geq 0[/tex]

[tex]2x\geq 6[/tex]

[tex]\dfrac{2x}{2}\geq \dfrac{6}{2}[/tex]

[tex]x\geq 3[/tex]             ...(i)

And,

[tex]x-3\neq 0[/tex]

Adding 3 on both sides, we get

[tex]x-3+3\neq 0+3[/tex]

[tex]x\neq 3[/tex]             ...(ii)

Using (i) and (ii), it is clear that the function is defined for all real values which are greater than 3 but not 3.

Therefore, the smallest possible integer value for x is 4.

Helpekksdjfkfodldkdkdodidididisj Help

Answers

Answer:

The answers to your questions are given below.

Step-by-step explanation:

1. m∠1 and m∠2 are complementary. This statement was given from the question.

2. m∠1 + m∠2 = 90°. Complementary angles add up to give 90°.

3. m∠2 = 74°. This was given in the question.

4. m∠1 + 74 = 90°. Since m∠1 and m∠2 are complementary. Their sum will add up to give 90°

5. m∠1 = 16°

We can prove m∠1 = 16° as shown below:

m∠1 + m∠2 = 90° (complementary angles)

m∠2 = 74°

m∠1 + 74 = 90°

Collect like terms

m∠1 = 90 – 74

m∠1 = 16°

Think of a two-digit number. What is the probability that it has different digits?

Answers

Answer:

9/10

Step-by-step explanation:

The first two digit number is 10 and the last is 99. That's a total of 99-10+1 numbers in all. That simplifies to 90. (Just like if we wanted to see how many numbers was 3,4,5, we would do 5-3+1=3 to get the total number.

Anyways, let's consider first how many 2 digjt numbers whose digits are equal. You have 11 22,33,44 55,66,77,88,99 which is 9 numbers total.

So the amount of 2 digits number whose digits differ is 90-9=81.

The probability that a 2 digit number have different digits is 81/90.

This can reduce. Divide top and bottom by 9 giving 9/10.

The length of the path of the first swing of the bob of a pendulum is 0.6 in. Each
succeeding swing is only 0.9 as long as the preceding one. How far will the bob travel in the
first six swings?

Answers

Answer:

0.3188646

Step-by-step explanation:

an=a×r^n-1

a6=0.6×0.9^5

=0.354294

1st swing: 0.6

2nd swing: 0.9×0.6=0.54

3rd swing: 0.9×0.54= 0.486

4th 0.9×0.486= 0.4374

5th 0.9×0.4374= 0.39366

6th 0.9×0.39366=0.354294

Brainliest please~

The bob travel in the first six swings will be 0.35 inches.

What is a geometric sequence?

Let a₁ be the first term and r be the common ratio.

Then the nth term of the geometric sequence is given as,

aₙ = a₁ · (r)ⁿ⁻¹

The length of the path of the first swing of the bob of a pendulum is 0.6 in.

Each succeeding swing is only 0.9 as long as the preceding one.

The first term is 0.6 and the common ratio is 0.9.

Then the bob travel in the first six swings will be

a₆ = 0.6 × (0.9)⁶⁻¹

a₆ = 0.6 × (0.9)⁵

a₆ = 0.6 × 0.59

a₆ = 0.35

The bob travel in the first six swings will be 0.35 inches.

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A certain prescription drug diminishes in the system at a rate of 25% per hour. If a person was administered 1450mg of the drug, how much will remain in 4 hours? How many hours will it take for the amount of the drug in their system to be less than 5mg?

Answers

9514 1404 393

Answer:

459 mgabout 20 hours

Step-by-step explanation:

The decay factor is 1 -25% = 0.75 per hour, so the exponential equation can be written ...

  r(t) = 1450·0.75^t . . . . . milligrams remaining after t hours

__

a) After 4 hours, the amount remaining is ...

  r(4) = 1450·0.75^4 ≈ 458.79 . . . mg

About 459 mg will remain after 4 hours.

__

b) To find the time it takes before the amount remaining is less than 5 mg, we need to solve ...

  r(t) < 5

  1450·0.75^t < 5 . . . . use the function definition

  0.75^t < 5/1450 . . . . divide by 1450

  t·log(0.75) < log(1/290) . . . . . take logarithms (reduce fraction)

  t > log(1/290)/log(0.75) . . . . . divide by the (negative) coefficient of t

  t > 19.708

It will take about 20 hours for the amount of the drug remaining to be less than 5 mg.

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