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valentina_108 [34]
3 years ago
7

Solve the system by substitution -x - y - z= -8 -4x + 4y + 5z = 7 2x + 2z = 4

Mathematics
1 answer:
Stella [2.4K]3 years ago
5 0

First:

2x + 2z = 4

2(x+z)=4

x+z=4/2

x=2-z

-x - y - z=  -8

-(2-z)-y-z= -8         replace x

-2+z-y-z= -8          (cancel z)

-2-y= -8

6 = y

Then:

-4x + 4y + 5z = 7  replace x and y

-4(2-z)+4*6 + 5z = 7

-8 + 4z + 24 + 5z = 7

16 + 9z = 7

9z = 7 - 16

9z = -9

z = -9/9

z= -1

Finally

x= 2-z  replace z

x = 2- (-1)

x = 3

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Determine if the equation below is a function with independent variable x. If so, find the domain. If not, find a value of x to
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Answer:

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Step-by-step explanation:

A function has one output per input.

If we are trying to determine if the given is a function of x, then x is the input.

However I can get two outputs from plugging in x=3.

3^2+y^2=25

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y^2=25-9

y^2=16

Take the square root of both sides:

y=\pm \sqrt{16}

y=\pm 4.

So input x=3 yields y=4 and y=-4.

Since this input has more than one output then the given is not a function of x.

----Also!

If you graph the equation, it is a circle with radius 5 and center (0,0). So I could I plug in any number for x between -5 and 5 excluding -5 and 5 which would yield only one output each. Since plugging in either one gives:

(\pm 5)^2+y^2=25

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There is only one value y such that when you square it gives you 0. That is 0.

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8 0
3 years ago
3y-15-6x in slope intercept form
ASHA 777 [7]
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Im going to guess the equal sign  because you didn't include it. I can fix the answer is I was wrong.

3y-15=6x    (add 15 to both sides)

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2 years ago
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8 0
2 years ago
Pls answer with real answers only thank you
aev [14]
Answer: 32.35 cm^2

Step by step:

Find the area of the rectangle first.

A= L • W
A= 11 • 4.2
A= 46.2 cm^2

Then find the area of the circle. The formula is A= pi (r)^2. The diameter of the circle is 4.2 cm because looking at the width of the rectangle it fits into the circle as well.

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Then you would subtract 13.85 from 46.2 to find the shaded portion.

Hope this helps :))

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