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Naya [18.7K]
3 years ago
15

12x-20y=108 3x+ky=27 what is k

Mathematics
1 answer:
Sedaia [141]3 years ago
3 0

Let's look at the second equation and try multiplying it by 4:

4 * (3x + ky) = 4 * 27

Which gives us:

12x + 4ky = 108

This looks almost exactly like the first equation except that instead of -20y, there is 4ky. We could try making them equal to each other and solving for k:

-20y = 4ky

-20 = 4k

k = -5

Then, the answer is k = -5.

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Margaret [11]

Answer:

17xn

Step-by-step explanation:

7 0
3 years ago
Match the term with the definition.
maria [59]
1- Line:
A line is a one dimensional figure that is formed by joining an infinite set of points.
It has no start and no end.
Answer:
Line ..............> A) infinite number of points extending in opposite directions that has only one dimension

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Answer:
Line segment .........> D) a part of a line that has two endpoints

3- Ray:
A ray is also a one dimensional shape. A ray usually has a start point but no end point.
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A vertex is a term that is used to refer to the point where the two rays forming an angle meet.
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Hope this helps :)
4 0
3 years ago
A rectangular box with a volume of 684 ftcubed is to be constructed with a square base and top. The cost per square foot for the
SCORPION-xisa [38]

Answer:

The dimensions of the rectangular box is 36.23 ft×36.23 ft×4.345 ft.  

Minimum cost=2046.16 cents      

Step-by-step explanation:

Given that a rectangular box with a volume of 684 ft³.

The base and the top of the rectangular box is square in shape

Let the length and width of the rectangular box be x.

[since the base is square in shape,  length=width]

and the height of the rectangular box be h.

The volume of rectangular box is = Length ×width × height

                                                      =(x²h) ft³

x^2h=684\Rightarrow h=\frac{684}{x^2}  (1)

The area of the base and top of rectangular box is = x² ft²

The surface area of the sides= 2(length+width) height

                                               =2(x+x)h

                                               =4xh ft²

The total cost to construct the rectangular box is

=[(x²×20)+(x²×15)+(4xh×1.5)] cents  

=(20x²+15x²+6xh) cents

=(25x²+6xh) cents

Total cost= C(x).

C(x) is in cents.

∴C(x)=25x²+6xh

Putting h=\frac{684}{x^2}

C(x)=25x^2+6x\times\frac{684}{x^2} \Rightarrow C(x)=25x^2+\frac{4104}{x}

Differentiating with respect to x

C'(x)=50x-\frac{4104}{x^2}

To find minimum cost, we set C'(x)=0

\therefore50x-\frac{4104}{x^2}=0\\\Rightarrow50x=\frac{4104}{x^2}\\\Rightarrow x^3=\frac{4104}{50}\Rightarrow x\approx 4.345 ft.

Putting the value x in equation (1) we get

h=\frac{684}{(4.345)^2}

 ≈36.23 ft.

The dimensions of the rectangular box is 36.23 ft×36.23 ft×4.345 ft.  

Minimum cost C(x)=[25(4.345)²+10(4.345)(36.23)] cents

                               =2046.16 cents      

5 0
3 years ago
What is 43434 x 21387128930523122222 and the first person to answer will get a brainliest from me!!!!!!!!!!!!!1
Solnce55 [7]

Answer:

9.2892856e+23

Step-by-step explanation:

have a good day!

3 0
3 years ago
Read 2 more answers
I need to know the measures of all the angles in the figure
Nesterboy [21]
X=17
Angle E= 155°
Angle G=57°
Angle H=58°
3 0
3 years ago
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