K
Solve the matrix equation AX = B for X.
1 1
[42]
X =
A =
ہلے
B=
23
78

KSolve The Matrix Equation AX = B For X.1 1[42]X =A =B=2378

Answers

Answer 1

Answer:

Step-by-step explanation:

I'm impressed that they make you do this in H.S.    Linear Algebra.   it's good for more complex math .   so that's why i'm impressed.   Is this an AP class?  

Ax=B is our formula.   we need to know something about x,  it's size

so we look at rows and columns of A,   2x2   , also we need to know about B as well it's also 2x2

so now we know, that   a matrix  A, of  size  2x2,  *x = B of size 2x2

2x2*x=2x2   ....   2x2|2x2   since the two inside number match, we can do this multiplication,  and the two ouside numbers tell us the size of  x... it's also a 2x2.  I know, a lot of explaining to just get 2x2.   Maybe that is obvious, and i'm mansplaining,  :DD  ,  but I don't know what you know.

I'll put big subscripts on my matrix variable so you can see it well.  You understand the subscript is the element location in the matrix , right?  1,1 is just the top left corner element of the matrix.  ect , ect.

so now we need,  a1,1 * x1,1 + a1,2 * x2,1   = 2  in b1,1

then we need   a2,1 * x1,1 + a2,2 * x2,1 = 7  in b2,1

next we need a1,1 * x1,2 + a1,2 * x2,2   = 3  in b1,2

finally we need a2,1 * x2,1 + a2,2 * x2,2   = 8  in b2,2

X =  [tex]\left[\begin{array}{ccc}\frac{3}{2} &1\\\frac{1}{2} &2\end{array}\right][/tex]   I did that by observation.   have you learned any RREF methods yet?


Related Questions


5. Gabi will graph f(x) = x and m(x) = f(x). Mark each statement as true or false. If false,
rewrite as true in the space below.
a. The slope of m(x) will be steeper than f(x).
_b. The y-intercept of m(x) will be units up from f(x).
d. g(x) = f(x − 3)

Answers

The Slope of the first function is greater than the slope of the second function.  We can say that the function f(x) =x is steeper than the second function

What is a Slope?

A line's steepness and direction are measured by the line's slope. Without actually using a compass, determining the slope of lines in a coordinate plane can assist in forecasting whether the lines are parallel, perpendicular, or none at all.

Any two different points on a line can be used to calculate the slope of any line. The ratio of "vertical change" to "horizontal change" between two different locations on a line is calculated using the slope of a line formula.

A line's slope is determined by how its y coordinate changes in relation to how its x coordinate changes. y and x are the net changes in the y and x coordinates, respectively. Therefore, m = y/x, where m is the slope, can be used to express the change in the y coordinate with regard to the change in the x coordinate.

Take notice that tan = y/x.

In the given question, we have: two functions:

So, finding the slope of each of the functions;

The slope of the first function;  f(x) =x is 1;

The slope of the second function: m(x) =[tex]\frac{3}{5} f(x)[/tex];
Since the Slope of the first function is greater than the slope of the second function.  We can say that the function f(x) =x is steeper than the second function because the graph depends on the slope.

Hence,

the Slope of the first function is greater than the slope of the second function.  We can say that the function f(x) =x is steeper than the second function.

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Determine the function below that has a domain of a 2-4.
A f(x)=√x-1-4
B f(x)=1-√√x+4
f(x)=1+√x-4
D f(x)=√-4+x−1

Answers

The answer is D …………..

a train is 2500m long crosses a platform whose length is 1900 meters in 40 seconds . if a dog is running at the speed of 6 m\s in the direction of the train and the train is 936 meters away from the dog , then how much time will the train catch up with the dog

Answers

The train will catch up with the dog in 1.996 seconds

How to determine how much time it will take the train to catch up

The problem is solved using the formula for speed which is

distance / time

speed of the train = length of track / time

= 1900 / 40

= 475 m/s

speed of the dog is given to be 6 m/s

The relative velocity = 475 - 6 = 469 m/s

The time to catch up is calculated using relative velocity

469 * time = 936 meters

time = 936 / 469

= 1.996 seconds

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Meshea sold 12 dresses in 120 minutes at this rate how many hours will it take her to sell 144 dresses

Answers

Answer: 144 dresses in 1440 minutes.

Step-by-step explanation:

Divide 144 and 12 you get 12. So you multiply 12 and 120 and you get 1440.

The rate is 120min/12dresses. Let's simplify it.

12/120 = 10min/1dress (or just 10)

Lets use this rate for 144 dresses

10 x 144 = 1140

It will take 1440 minutes to sell 144 dresses.

From Monday to Thursday the debts of a snowdrift changed by -8 inches. From Thursday to Friday, the depth changed by half as much. What is the oh angle in the depth of the snowdrift from Monday to Friday?

Answers

The depth of snowdrift changed from Thursdays to Friday by -4 inches

The change of depth of snowdrift from Monday to Thursday = -8  inches

From Thursday to Friday, the depth changed by half as much

The equation is the mathematical statement that shows the relationship between two expression with and equal sign. The equation may consist of variables, numbers and arithmetic operators

Then the equation will be

The change of depth of snowdrift from Thursday to Friday = -8 /2

Here we have to use the division

Divide the terms

The change of depth of snowdrift from Thursday to Friday = -4 inches

Hence, depth of snowdrift changed from Thursdays to Friday by -4 inches

The complete question is :

From Monday to Thursday, the depth of a snowdrift changed by -8 inches. From Thursday to Friday, the depth changed by half as much. What is the change in the depth of the snowdrift from Thursday to Friday?

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A shop sells tins of paint in 2 litre and 5 litre cans. The manager checks the amount of paint he
has in stock, and finds that there are 500 cans altogether. These cans hold a total of 1420 litres of
paint. By forming and solving a pair of simultaneous equations, find the number of each size of
can in stock.

Answers

Answer:

360 of 2 liter cans and 140 of 5 liter cans

Step-by-step explanation:

Let the number of 2 liter cans be x and 5 liter cans be y.

Number of cans:

x + y = 500

Amount of paint:

2x + 5y = 1420

Solve the system by elimination, double the first equation and subtract from the second one:

2x + 5y - 2x - 2y = 1420 - 2*5003y = 420y = 420/3y = 140

Find x:

x + 140 = 500x = 500 - 140x = 360

-0.6a^2b * (-10ab^2)

please help :)

Answers

Answer:

evaluation or perhaps difference

Step-by-step explanation:

ex: 6b 2a 2b+1

diff: 6(2b+1)b 2 a 2b

Maria is renting kayaks from a local shop that charges a $10 fee, plus an hourly rate of $7. 50. For how long can maria rent the kayak if she pays a total of $70?.

Answers

Answer:

8 hours

Step-by-step explanation:

We can use an algebraic equation to solve this problem.

7.5x + 10 = 70

7.5x + 10 (-10) = 70 (-10)

7.5x (/7.5)= 60 (/7.5)

x = 8

Answer:
8 hours
Step-by-step explanation:
We can use an algebraic equation to solve this problem.
7.5x + 10 = 70
7.5x + 10 (-10) = 70 (-10)
7.5x (7.5)= 60 (17.5)
x = 8

A 2-pint bucket of paint costs $11.08. What is the price per cup?

Answers

The price per cup for a 2-pint bucket of paint costs $11.08 is $2.77.

How to calculate the price per cup?

It should be noted that 1 pint = 2 cup

In this case, 2-pint bucket will be:

= (2 × 2)

= 4 cups.

Therefore, 4 cups cost $11.08.

The price per cup will be:

= Total cost / Number of cups

= $11.08 / 4

= $2.77

The price is $2.77.

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lisa receives a salarry of rs 9500 per month plus a commision of 10 % on all sales. For te month of December, she earns rs 14000. find her total sales in december

Answers

Total earning = Salary + 10% of sales

According to question, we have

14000 = 9500 + 10% of sales

4500 = 0.1 sales

sales = 4500*10 = 45000

So, her total sales was Rs 45000

a stats 10 test has 4 multiple choice questions with four choices with one correct answer each. if we just randomly guess on each of the 4 questions, what is the probability that you get exactly 1 question correct? find the nearest answer.

Answers

if we just randomly guess on each of the 4 questions, Then the probability that you get exactly 1 question correct is 1/4.

Probability formula: P(E) = favourable outcomes/Total outcomes

The number of questions is 10

The options for each question are 4.

Possible answers are 1.

Then,

favourable events = 1 × 10= 10

Total events = 4× 10= 40

Now, find the probability by putting the values as follows:

P(E) = favourable outcomes/Total outcomes

P(E) = 10/40

P(E) = 1/4

Therefore, the probability of doing all questions correct is 1/4

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Below, the two-way table is given for a class
of students.
Sophomore
Freshmen
Male
4
Female 3
Total
6
4
17
Juniors Seniors Total
2
6
2
3
If a female student is selected at random, find the
probability that the student is a senior.
P(Senior | Female ) = [? ]%
Round to the nearest whole number.
Enter

Answers

Answer:

19%

Step-by-step explanation:

Of the female students, there are:

3 freshmen4 sophomores6 juniors3 seniors

Out of 16 total students, 3 are juniors, so the probability is [tex]\frac{3}{16} \approx 19\%[/tex]

24) The cost in millions of dollars for a company to manufacture x thousand automobiles is given by
the function C(x) = 3x^2 - 30x + 200. Find the number of automobiles that must be produced to
minimize the cost.
A) 15 thousand automobiles
C) 5 thousand automobiles
B) 125 thousand automobiles
D) 10 thousand automobiles

Answers

For minima,

C'(x) = 0

6x-30 = 0

x = 5

If C"(x) >0, then minima

So, C"(x) = 6 > 0

So, for x = 5 , thr value of C(x) will be minimum.

Option C is correct

Can anyone please help me with this? I don't get it.

Answers

Answer:

739

Step-by-step explanation:

2217 (weight) / 3 ( # of blocks)

A number is raised to the third power, then subtracted from 15 to get 7. What is the number squared?

Answers

Answer:

4

Step-by-step explanation:

Let x be the unknown number.

[tex]\begin{aligned}&\textsf{A number is raised to the third power}: & x^3&\\&\textsf{Subtracted from 15}: & 15-x^3&\\&\textsf{To get 7}: & 15-x^3&=7\end{aligned}[/tex]

Solve the found equation for x:

[tex]\begin{aligned}&\textsf{Given}: & 15-x^3&=7\\&\textsf{Subtract $15$ from both sides}: & -x^3&=-8\\&\textsf{Divide both sides by $-1$}: & x^3&=8\\&\textsf{Rewrite $8$ as $2^3$}: &x^3&=2^3\\&\textsf{Cube root both sides}: & x&=2\end{aligned}[/tex]

Therefore, the number squared is:

[tex]\implies x^2=2^2=4[/tex]

Write the equation for the following graph

Answers

Answer:

y = 4x - 6

Step-by-step explanation:

linear equation:

y = mx + b

1. find the slope m

first select two point

im gonna take point 1 (-1,-7) and point 2 (3,9)

m = (y2-y1)/(x2-x1)

m = (9-(-7))/(3-(-1)) = 16/4 = 4

2. find b

first select a point

im gonna reuse point 2 (3,9)

y = mx + b

9 = 5(3) + b

9 = 15 + b

b = 9 - 15 = -6

3. keep x y, substitute m,b to linear equation

y = 4x - 6

The tap can fill up the bathtub in 22 minutes. The capacity of the bathtub is 176 L

How much water is added to the tub per minute?

Answers

Answer:

8.8 L

Step-by-step explanation:

volume/time

176/22

=8.8

There are 50 tudent in cla. Boy make up 20% of the cla. 60% of the boy wear glae. How many boy in the cla wear glae?

Answers

The boys in the class that wear glae are 6 people.

The boys in the class that wear glae can be calculated as follows:

First we should calculate how many boys there are in the class. We can calculate it by multiplying the percent of the boys to the total students.

Boys in the class = [tex]\frac{20}{100} X 50[/tex] = 10 people.

Thus, we can calculate the boys who wear the glae by multiplying the percent of the boys wearing glae of the boys in the class.

Boys wear glae = [tex]\frac{60}{100} X 10[/tex] = 6 people.

Hence, The boys in the class that wear glae are 6 people.

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Put the following equation of a line into slope-intercept form, simplifying all fractions. 9y−3x= −54

Answers

The equation of the line into slope-intercept form is y = x/3 - 6

What are linear equations?

Linear equations are equations that have constant average rates of change.

Note that the constant average rates of change can also be regarded as the slope or the gradient

How to put the equation of a line into slope-intercept form?

From the question, we have the following equation that can be used in our computation:

9y−3x= −54

Rewrite properly

This gives

9y - 3x = -54

Divide through the equation by 3

So, we have the following representation

9y/3 - 3x/3 = -54/3

Evaluate

3y - x = -18

To rewrite as slope-intercept form is to make y the subject

So, we have

3y = x - 18

Divide through the equation by 3

So, we have the following representation

y = x/3 - 6

Hence, the equation is y = x/3 - 6

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Help me solve this please

Answers

Step-by-step explanation:

let's use the law of sine :

a/sin(A) = b/sin(B) = c/sin(C)

so,

5.4/sin(K/2) = 12.3/sin(M1)

8.2/sin(K/2) = x/sin(M2)

M1 + M2 = 180 (as complementary angles or linear pair)

M2 = 180 - M1

sin(K/2) = 5.4×sin(M1)/12.3

sin(K/2) = 8.2×sin(M2)/x

therefore

5.4×sin(M1)/12.3 = 8.2×sin(180 - M1)/x

since sin(a) = sin(180 - a)

5.4×sin(M1)/12.3 = 8.2×sin(M1)/x

and then

5.4/12.3 = 8.2/x

x×5.4 = 8.2×12.3

x = 8.2×12.3/5.4 = 18.67777777... ≈ 18.7

Step-by-step explanation:Step-by-step explanation:

let's use the law of sine :

a/sin(A) = b/sin(B) = c/sin(C)

so,

5.4/sin(K/2) = 12.3/sin(M1)

8.2/sin(K/2) = x/sin(M2)

M1 + M2 = 180 (as complementary angles or linear pair)

M2 = 180 - M1

Please answer this question

Answers

Answer:

x=9

y=-5

Or

(9,-5)

Step-by-step explanation:

-x+y=-14

+x.    +x

y=x-14


2x-3(x-14)=33

2x-3x+42=33

-x+42=33

   -42. -42

-x=-9

/-1. /-1

x=9


-(9)+y=-14

+9.      +9

y=-5

Hopes this helps please mark brainliest

suppose that the radius is expanding at a rate of 0.6 inches per second. how fast is the volume changing when the radius is 2.3 inches? use at least 5 decimal places in your answer.

Answers

Using the theories of Application of derivative,we got that  59.11221inches³/sec  is rate of volume changing when the radius is 2.3 inches.

We are given rate of change of radius (dr/dt)=0.6inches

We know very well that volume of sphere is given by (4/3)πr³

where r is the radius of the sphere.

Now, differentiating the volume with respect to radius, we get

=>dV/dr=4πr²

=>dV/dt=(dv/dr)·(dr/dt)

=>dV/dt=4πr².(dr/dt)

We are given that dr/dt=0.6inches/sec

So, dV/dt=4πr²·(0.6)

Now, putting values of r=2.3

 dV/dt=4π(2.3)²×(0.6)

=>dV/dt=4×3.14×2.3×2.3×0.6

=>dV/dt=59.11221inches³/sec

Hence, if we suppose suppose that the radius is expanding at a rate of 0.6 inches per second, the volume is changing at the rate of 59.11221inches³/sec when the radius is 2.3 inches.

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Can someone please help

Answers

After solving the value of x is 2.

From the figure:

Let ABCDE be the figure such that:

AB = 6x , BC = 6 , CD = 4,and DE = CE - CD  = 12 - 4 = 8.

BD and AE are parallel lines such that:

AB/BC = ED/CD

6x/6 = 8/4

x = 8/4

x = 2.

Therefore After solving the value of x is 2.

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12 Cookies

4 kids are trying to share amongst themselves 12 cookies. How many does each kid get? Write a story to describe the situation.

Answers

Kayla brought cookies to school. She only gave cookies to her friends but she had too many cookies, now they figure out how to share.

Write 36 a product of it' prime factor. Write the factor in order, from mallet to larget

Answers

The factor of 36 in order from smallest to largest is 2 × 2× 3× 3.

Prime factor:

Factors are the numbers you multiply together to get another number. In simple words, a prime factor is finding which prime numbers multiply together to make the original number.

Here we have to find the prime factor 36.

That is we have to find the smallest multiplication of digits to get the value.

36 = 2 × 2 × 3 × 3

Therefore the prime factor is 2 × 2×3×3.

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what is the value of x in the equation 0.5x+3=4.5?

Answers

x=3

.5(3)= 1.5
1.5+3=4.5

Answer:

x = 3

Step-by-step explanation:

Collect like terms

0.5x = 4.5 - 3

0.5x = 1.5

Divide both sides by 0.5

0.5x/0.5 = 1.5/0.5

x = 3

Using fractions,

1/2x = 9/2 - 3

1/2x = 3/2

Divide both sides by 1/2

x = 3/2÷1/2

Reciprocate

x = 3/2 × 2/1

x = 6/2

x = 3

Ninety five percent of students in statistics scored between 62 pts and 90 pts. Assuming this data is normally distributed, what are the mean and standard deviation?.

Answers

The mean is 76 and the standard deviation is 7.

What is mean and standard deviation?

The standard deviation in statistics is a measurement of how much a group of values can vary or be dispersed. A low standard deviation suggests that values are often close to the set's mean, whereas a large standard deviation suggests that values are dispersed over a wider range.

In mathematics, particularly in statistics, there are various types of means. Each mean summarizes a particular set of data, frequently to help determine the overall significance of a particular data set.

Let, 95% of students in statistics scored between 62 and 90 points.

Here,

Mean = [tex]\frac{62+90}{2} = \frac{152}{2} = 76[/tex]

And the standard deviation is,

SD = [tex]\frac{90-76}{2}= \frac{14}{2} = 7[/tex]

Hence, the mean is 76 and the standard deviation is 7.

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the rectangular floor of a classroom is 30 feet in length and 20 in width. A scale drawing
of the floor has a length of 15 inches. what is the area in square inches, of the floor in the scale drawing

Answers

Answer: 150 square inches

Step-by-step explanation:

Set up the proportional ratios (convert feet to inches first):

30 ft = 360 inches (there are 12 inches in 1 foot)

20 ft = 240 inches (I'm assuming there is an error in the question and the width is 20 ft, NOT 20 inches!)

360/15 = 240/x

x is the width of the scaled down rectangle

solve for x:

360x = 3600

x = 10 in

Now calculate Area = length x width

A = 15 x 10 = 150 square inches

Nolan has five more quarters and dimes and seven fewer nickels and dimes. He has 25 coins. How many of each coin does he have? How much money in dollars and cents is it worth?

Answers

Answer:

9 dimes, 4 nickels, 12 quarters

90 cents + 20 cents + 300 cents = 410 cents = $6.83

Step-by-step explanation:

q=5+d

n=d-7

q+n+d=25

5 + d + d - 7 + d = 25

3d-2=25

3d=27

d=9

25 - 9 = 16 nickels and quarters

q + n = 16 ---> q=16-n

n=d-7 ---> d=n+7

q=5 + n + 7

q=n+12

n+12 = 16-n

2n=4

n=4

25-(9+4)= 12 quarters

Answer:

He has 2 nickels, 9 dimes, and 14 quarters, with a total value of $4.50

Step-by-step explanation:

I am going to assume that the "and" in "five more quarters and dimes" and the "and" in "seven fewer nickels and dimes" is actually "than" because otherwise, there is no context in this question. If my answer is incorrect, please tell me how to correctly interpret this question.

In this scenario, the "and" in "five more quarters and dimes" and the "and" in "seven fewer nickels and dimes" is actually "than."

Amount of nickels - x

If there are seven fewer nickels than dimes, the amount of dimes is x + 7. There are five more quarters than dimes, so the amount of quarters is x + 7 + 5, which equals x + 12.

x + x + 7 + x + 12 = 253x + 19 = 253x = 6x = 2

Therefore, there are 2 nickels. Now we must figure out the number of quarters and dimes.

x + 7 = 9

x + 12 = 14

There are 9 dimes and 14 quarters.

Nickels are each worth 5 cents. 2 times 5 is 10 cents.

Dimes are each worth 10 cents. 9 times 10 is 90 cents.

Quarters are each worth 25 cents. 14 times 25 is 350 cents.

Now, we add. 10 + 90 + 350 = 100 + 350 = 450.

REMEMBER, THIS IS IN CENTS. WE MUST STILL CONVERT IT INTO DOLLARS.

450 divided by 100 is $4.50

……………………………………………………..

Answers

Answer:

-11, -2, 3, 6

-16, -5, 19, 21

Step-by-step explanation:

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