Use cramers rule to solve 4x+3y=4 -3x-y=7 show your work

Answers

Answer 1

Answer: $\left\{\begin{array}{ccc}4x+3y=4\n-3x-y=7\end{array}\right\n\nD= \left|\begin{array}{ccc}4&3\n-3&-1\end{array}\right|=(4)(-1)-(-3)(3)=-4+9=5\n\nD_x=\left|\begin{array}{ccc}4&3\n7&-1\end{array}\right|=(4)(-1)-(7)(3)=-4-21=-25\n\nD_y=\left|\begin{array}{ccc}4&4\n-3&7\end{array}\right|=(4)(7)-(-3)(4)=28+12=40\n\nx=(D_x)/(D)\Rightarrow x=(-25)/(5)=-5\n\ny=(D_y)/(D)\Rightarrow y=(40)/(5)=8$

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Find the area of the square s = (2w - 4)

Answers

4wsquared- 16w+16..........

What is the thousandth positive odd number ?

Answers

so the formula for odd numbers is 2n

the nth term is 2n
the first odd number is 2(1)=2
second=2(2)

so the thousanth odd number is 2(1000)=2000

Find the limit of the function algebraically. limit as x approaches negative six of quantity x squared minus thirty six divided by quantity x plus six.

Answers

$lim_(x \rightarrow -6) (x^2-36)/(x+6) \n =lim_(x \rightarrow -6) ((x-6)(x+6))/(x+6) \n =lim_(x \rightarrow -6) (x-6) \n =-6-6=-12$

Answer:

-12

Step-by-step explanation:

$\lim_(x \to \ -6) (x^2-36)/(x+6)$

We factor the numerator and try to simplify the fraction as much as we can.

$x^2-36 = x^2 - 6^2$

Apply a^2 - b^2 formula (a+b)(a-b)

$x^2-36 = x^2 - 6^2=(x+6)(x-6)$

$\lim_(x \to \ -6) ((x+6)(x-6)/(x+6)$

Cancel out x+6 from top and bottom

$\lim_(x \to \ -6)(x-6)$

Plug in -6 for x

-6-6 = -12

The lenght of a rectangular classroom floor is 19 feel less than twice the width which expression repersents the area of the classroom floor

Answers

w*(2w-19)=A. Just make the width a variable and write out the relationship it has with the length

Which of the following is a common incorrect answer given by students when solving the problem 8 -:- 1/2= a. 16 b. 4 c. 1/4 d. 1/16

Answers

Answer:

The common incorrect answer given by students when solving the problem 8 -:- 1/2 is option b. 4.

Step-by-step explanation:

Final answer:

The common incorrect answer given by students is 16 when solving the problem 8 -:- 1/2. Therefore, the correct option is A

Explanation:

The common incorrect answer given by students when solving the problem 8 -:- 1/2 is a. 16.

To solve this problem, we need to remember the rules of division. When dividing by a fraction, we actually multiply by its reciprocal. So 8 -:- 1/2 is the same as 8 x 2/1, which equals 16.

Therefore, the correct answer is a. 16.

Learn more about Solving division problems here:

brainly.com/question/11228573

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Alejandro has 3 times as many playlists as Derrick does. Alejandro has 24 playlists. If d = the number of playlists Derrick has, which mathematical sentence expresses the information above?

Answers

Answer:

Derrick has 8 playlists in his possession.

Step-by-step explanation:

If Derrick as x amount of playlists, then if Alejandro has 3 times as many playlists as Derrick then he has 3x. Now if Alejandro has 24 playlists we can create the following mathematical expression to figure out how many playlists Derrick has.

$3x = 24$ .... divide both sides by 3

$x = 8$

We can now see that Derrick has 8 playlists.

I hope this answered your question. If you have any more questions feel free to ask away at Brainly.

That's it
3*d=24
d=24/3
d=8

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