Anyone good at math here that can help me?

kyubbi sagemode

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Can anyone help me with this it's on my Finals study guide and I don't understand it at all

A system of linear inequalities is shown below.
x - y > 3

y + x ≀ 2

Describe the steps to graph the solution set to the system of inequalities.
 

Sound

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My skills are rusty but it's something like this.
x - y > 3

y + x ≀ 2


x = 2-y β†’ 2 - y > 3 β†’ -y > 3-2 β†’ y < -1

y + x ≀ 2 β†’ y=2 - x β†’ x - 2 - x > 3 β†’ 2x > 3 β†’ x < -3/2



You should learn the chapter you got this.
 
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Wolfus

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I'll help you out.

Lets start by isolating x in the first inequation

x > 3 + y

Now, let's do the same in the second on

x</= 2-y

Ok then. But if x</= 2 - y, and the same x > 3 + y, then

3 + y< 2- y

Then, we have 2y< -1, y<-1/2

In that case, if y< -1/2, and x> 3+y, then x> 5/2 (we replaced "y's limit value" in the inequation with x)

You can check it out by replacing x and y under those conditions
 

Wolfus

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My skills are rusty but it's something like this.
x - y > 3

y + x ≀ 2


x = 2-y β†’ 2 - y > 3 β†’ -y > 3-2 β†’ y < -1

y + x ≀ 2 β†’ y=2 - x β†’ x - 2 - x > 3 β†’ 2x > 3 β†’ x < -3/2



You should learn the chapter you got this.
You made a mistake there buddy. When you replaced x. You forgot about the first "-y"
 
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Sound

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You made a mistake there buddy. When you replaced x. You forgot about the first "-y"

Yes you're right. I solved on a paper and afterwards resolved on the computer. I wondered why I got a different result.
OP go with this guy solution. Anyway I fixed it.
x - y > 3
y + x ≀ 2


x = 2 - y

2 - y - y > 3

2 - 2y > 3

-2y > 3 - 2

-2y >1

y < -1/2



y = 2 - x

x-2 - x > 3

-2x -2 > 3

-2x >3+ 2

-x > 5/2

x < - 5/2
 
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Wolfus

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Yes you're right. I solved on a paper and afterwards resolved on the computer. I wondered why I got a different result.
OP go with this guy solution. Anyway I fixed it.
x - y > 3
y + x ≀ 2


x = 2 - y

2 - y - y > 3

2 - 2y > 3

-2y > 3 - 2

-2y >1

y < -1/2



y = 2 - x

x-2 - x > 3

-2x -2 > 3

-2x >3+ 2

-x > 5/2

x < - 5/2
Sorry, but there's another mistake there. When you replace y. It would be x-(2-x). Then 2x would be positive, resulting in x> 5/2
 
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