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3 years ago

If you were to solve the following system by substitution, what would be the best variable to solve for and from what equation?

Mathematics

1 answer:

VashaNatasha [74]3 years ago

7 0

Answer: B. x, in the second equation

Step-by-step explanation:

The given system :

$2x+6y=9...................(1)\\\\3x-12y=15.........................(2)$

To apply the substitution method , first we need to select the best variable and a equation which is easy to simplify.

From the given system equation (2) have all the numbers which are multiples of 3.

Then we divide 3 on both sides of equation (2), we get

$x-4y=5\\\\\Rightarrow\ x=4y+5$

Therefore, the best variable to solve for and from what equation is x, in the second equation.

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|5x|+5=45<br><br> can you explain this absloute value equation <br> i have a midterm

Ymorist [56]

So first, you get the absolute value to one side:
$|5x|+5=45\\
|5x|=40$

Next, set up two equations; One where the value inside the absolute value lines is positive, and another where it is negative, and solve both for the variable:
$|5x|=40\\5x=40\\x=\frac{40}{5}=8\\\\-5x=40\\x=\frac{40}{-5}=-8$

Your answers are 8 and -8, or +-8.

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2 years ago

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¿Can i get the answer?

NikAS [45]

Answer:

15.7

Step-by-step explanation:

5 x 3.14(pi) = 15.7

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2 years ago

What is the surface area of the figure shown? Plz answer asap

Luba_88 [7]

Answer:

$264\ cm^{2}$

Step-by-step explanation:

we know that

The surface area of the figure is equal to the lateral face of the triangular pyramid plus the lateral face of the rectangular prism plus the area of the base of the rectangular prism

step 1

Find the lateral face of the triangular prism

The lateral area is equal to the area of its four lateral triangular faces

$LA=4(\frac{1}{2}(6)(7))=84\ cm^{2}$

step 2

Find the lateral area of the rectangular prism

The lateral area is equal to the perimeter of the base multiplied by the height

$LA=(4)(6)(6)=144\ cm^{2}$

step 3

Find the area of the base of the rectangular prism

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step 4

Find the surface area

$84\ cm^{2}+144\ cm^{2}+36\ cm^{2}=264\ cm^{2}$

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2 years ago

State the slope and y intercept of the graph of 9-x=2y

jasenka [17]

The equation of a line is given by y = mx + c; where m is the slope.
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y = -1/2 x + 9/2
Therefore, the slope is -1/2 and the y-intercept is 9/2.

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3 years ago

X over 8 = -5 . What is X?

valkas [14]

Answer: 40

Step-by-step explanation:

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