tìm m để phương trình có 1 nghiệm duy nhất
x+2y-2z=2
3x+7y-z=5
2x+4y+mz=7

Answers

Answer 1

Rewrite the system of equations in matrix form.

[tex]\begin{bmatrix}1&2&-2\\3&7&-1\\2&4&m\end{bmatrix} \mathbf x = \mathbf b[/tex]

This system has a unique solution [tex]\mathbf x = \mathbf A^{-1}\mathbf b[/tex] so long as the inverse of the coefficient matrix [tex]\mathbf A[/tex] exists. This is the case if the determinant is not zero.

We have

[tex]\det(\mathbf A) = m+4[/tex]

so the inverse, and hence a unique solution to the system of equations, exists as long as m ≠ -4.


Related Questions

Triangle ABC has coordinates A(-2, -3), B(1, 1), and C(2, -1). If the triangle is translated 1 unit right and 3 units up, what are the coordinates of A'?

Answers

Answer:

answeris: C.(-6,-9)➡(6-9)

An arrow is shot vertically upward from a platform 45 feet high at a rate of
132 ft/sec. Use the quadratic function h(t)=−16t2+132t+45 to find how long it will take the arrow to reach its maximum height, and then find the maximum height. Round to the nearest tenth.

Answers

Answer:

486 feet will reached after 5.25 seconds, when rounded to nearest tenth would be 5.3

Step-by-step explanation:

6-4x=12+2x

Solve for x

Answers

6-4X = 12 + 2X
+4X. +4X
6= 12 + 6X
-12. -12
-6 = 6X

X EQUALS -1!

please help!

15 - (-20)

Answers

I think it should be 35
35, the two negatives cancel out if they are next to each other, making it a plus sign instead, so its 15 + 20 = 35

Use your work from above to find the sum of 501+502+503+…+800

Answers

Answer:

Step-by-step explanation:

Gauss n(n+1)/2

which is n? the last number of the sum

500(500 + 1)/2 = 125,250

800(800+1)/2 = 320,400

uh oh forgot to read the last one, give me a minute. done

(800 - 501 + 1)(800 + 501)/2

300(1301)/2 = 195,150

or

320,400 - 125,250 = 195,150

A 6-pack of ice cream sandwiches costs $3.86. What is the unit price, rounded to the nearest cent?


Answers

Answer: so either .64 or , .66,

Step-by-step explanation:

divide 3.86 by 6

Please find the correct answer will give high points, mark brainliest, give 4 stars, and hearts. PLS


Answers

Answer d is correct.
|0.35| is equal to 0.35, |-0.81| is equal to 0.81.
-|0.81| is equal to -0.81.
Answer d is correct because -|0.81| is equal to a negative number and is less than 0, and d is the only answer that states that

after how many years will £6,000.00 yield a simple interest of £900.00 at 3%​

Answers

Answer:

add 1 Century to divide £6 000 000

Answer:

the answer to your question is 105 I think sorry if it's not

Which table of ordered pairs represents a proportional relationship?
CS
Х
-2
-4
-6
у
4
16
36
х
-4
-6
-8
y
-8
-12
-18
Х
-3
-5
-7
y
5
3
1
X
-3
6
_9
у
12
24
36

Answers

Answer: A 2-column table with 3 rows.

Step-by-step explanation:

Find the GFC of 72 and 64

Answers

Answer:

8

Step-by-step explanation:

GCF of 64 and 72 is 8.

I hope it helps you..

WHAT IS THE EQUATION IN SLOPE INTERCEPT FORM FOT THE LINE THAT PASSES THROUGH THE POINTS (2,-2) AND (-3,-17)

Answers

Answer:

y = 3x - 8

Step-by-step explanation:

to find slope the equation (y2 - y1) / (x2 - x1) is used

this means change of y over change of x

[-17 - (-2)] / (-3 - 2)

(-17 + 2) / -5

-15 / -5 = 3

the slope is 3

to find slope intercept form you must find the y intercept

using y = 3x + b and plugging things in we can find it

we can plug in the first point

-2 = 2(3) + b

b is your y intercept

-2 = 6 + b

b = -8

Answer:

y = 3/1x - 8

steps:

(2,-2) (-3, -17)

x1. y1. x2. y2

y2-y1

x2-x1

-17 - -2 = -15. = 3

-3-2. -5. 1

(2,-2)

y= mx + b

-2 = 3/1(2) + b

-2 = 6 + b

-6 -6

-8 = b

y = 3/1x - 8

This is a glucose molecule. How many hydrogen atoms are in a molecule of glucose? A) 10. B) 11. C) 12. D) 13

Answers

Answer:

12 for sure

Step-by-step explanation:

I just know

A 6 sided die is rolled 2 times. What is the probability of getting a 1 both times ?

Answers

Answer:

Step-by-step explanation:  If you roll the die twice, the probability of getting a even number both times is (1/2)(1/2) ... A probability experiment consists of rolling a 6 sided die

In your own words what does pi 7 mean if it’s right I’ll give you brainliest

Answers

Answer:

10

Step-by-step explanation:

Maria finds a local gym that advertises 44 training sessions for $1393. Find the cost of 136 training sessions.

Answers

Answer:

$4305.60

Step-by-step explanation:

1393 divided by 44 = 31.6590909

that's how much for one training session

so to find the pay for 136 sessions you need to do 31.6590909 x 136

which is 4305.63636

if you round that, you get $4305.60

Which of the functions below have period pie check all that apply

Answers

There is no photo attached.

A

Triangle ABC is right-angled at A, and AD is the altitude from A to the hypotenuse BC.
Find x

Answers

Answer:

Step-by-step explanation:

5 x 6:30

Can somebody please help this is honestly due tomorrow

Answers

Answer:

I am almost completely sure its 4.

Step-by-step explanation:

I dont mind brainiests by the way

Please help me :)
What is the solution to this system of equations?

Answers

Answer:

The answer is D

Step-by-step explanation:

Plug in the values and see which one is correct.

This the right one click it so you can get it right

Answers

Answer:

The one highlighted yellow is the correct option

6 liters is to 72 km as 50 liters is to x km

The perimeter of a triangle is 71 cm. If the longest side of the triangle is 8 cm longer than five times the shortest side and the third side is 7 cm less than four times the shortest side. How long is the longest side of the triangle?

Answers

Answer:

43 cm

Step-by-step explanation:

If the longest side of the triangle is 8 cm longer than five times the shortest side

5s + 8

the third side is 7 cm less than four times the shortest side

4s - 7

The perimeter of a triangle is 71 cm

s + (4s - 7) + (5s + 8) = 71

Combine like terms

10s + 1 = 71

Subtract 1 from both sides

10s = 70

divide both sides by 10

s = 7

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

How long is the longest side of the triangle

5s + 8

5(7) + 8

35 + 8

43

Use the figure below to find the values of x and y

Answers

Answer:

x=68 and y = 112

Step-by-step explanation:

angles of a triangle must equal 180, so

52°+60°+x°=180

112+x=180 <-- subtract 112 to get x on one side.

x=68

To solve for y, a straight line = 180 so

68+y=180 --> just subtract 180-68

y=112

This morning, Megan and her dad had smoothies for breakfast. Megan made her smoothie with 1 cup of mango and 3 cups of strawberries. Her dad made a giant smoothie with 2 cups of mango and 6 cups of strawberries. Did the smoothies have the same ratio of mango to strawberries?

Answers

Answer:

Yes.

Step-by-step explanation:

a ratio is a comparison between two or more numbers or quantities

a. True
b. False​

Answers

The correct answer is true

Which equation represents the data in the table shown?
A) y = -2x
B) y = 2x + 3
C) y = -2x + 3
D) y = -2x - 3

Answers

Answer:

C

Step-by-step explanation:

the y-axis is getting smaller by 2 so its -2 and the x-axis is getting bigger by 1 so its -2 times 1 which is -2 but then 0=3 so the equation would be y = -2 + 3 :)

You charge $1625 on your credit card that adds 8.2% intere don't make any payments, what will your balance be after 4 years compounded continuously?"​

Answers

Answer:$2227.22

Step-by-step explanation: I answered your question in your comment. If its not right report it please.

Which of the following is equal to the expression below
(8 - 32014
A 40
B. 30
C 835
D. 1035

Answers

Answer:

C 835Which of the following is equal to the expression below

What is the algebraic expression for the following word phrase: "the product of x and the sum of 2 and y"?

Answers

Answer:

x(2+y)

Step-by-step explanation:

sum of 2 and y=2+y

product of x=x times expression

:. Answer =x(2+y)

Find all factors of 27.​

Answers

Answer:

all the factors of 27 is 1, 3 ,9,and 27

1 , 3 , 9 , 27 hope that helps you

A store is having a sale where movies are 15% off their original price a movie is on sale for 22.10$ what was the original price of the movie

Answers

Answer:

The answer is $26

Step-by-step explanation:

So, the price after the sale was $22.10 and to find the original price you have to divide the price by 1- the discount. So, I did $22.10/ 1-0.15. Then, I got $22.10/0.85 and then I divided them by each other and got $26.

Other Questions
20 points! :DNot sure how to do this. :/ joann is preparing a statement of cash flows as part of a homework assignment. she hopes to find a check figure that will help her assess the accuracy of her results. what should joann do to quickly find a check figure? Does international human rights law apply to lgbtq people? restated as a statement please Write two algebraic expressions that have -10m as one of the terms in their product. -7/10 + 7 2/3show all ur work what is coefficient of 10 and a constant of 5? which statement correctly compares the function shown on this graph with the function y = 3x - 6? PLLLSSS HELP ME I WILL GIVE BRAINIEST in the Fall of the year, leaves appear red, orange, yellow and brown because the chlorphyll decreases in the leaves and allows the --(blank)-- pigments to reflect mostly colors other than green.possible answers than can go in the blank are primary or accessory Explain how chemical properties and chemical changes are different? what do you mean by decimal number systemplease give answer what s the biggest capitol? Billy Bob just bought a new car his car costs $75,000. how much money will he pay in taxes for the car if the sales tax is 6%? Find the values of x and y. Lan is interested in teaching _______ because she loves working with children. Select the pair of homonym from the choices below: A. Alter,alter b. Big,enormous c. Long,short d. Eyes,nose Which is the most highly sensitive time within the developing embryo for the risk of malformation related to environmental teratogens Where did each political party stand on these key issues? Democrat Whig Your thoughtsRole of Federal governmentMarket economyNational bankTariffsSlaveryIndian Removal ActsNullification Please help me with this MATH question. Please help I am confused between option (b) and (c) studies show that _____________ is the optimal amount of stress that people need to positively promote their health and sense of well-being, which coincides with ______________ theory.