Solving system of linear inequalities

In summary, the conversation was about a question regarding solving a system of inequalities and determining which ordered pairs satisfy the system. The conversation also included a suggestion to plot the inequalities and the given points to verify the answer. The initial response was interpreted as rude, but it was explained that it was meant as an expression of incredulity due to the lack of information provided in the initial post. It was also stated that rudeness is not condoned and that the goal of the conversation and the website is to provide a friendly atmosphere for math help. It was also mentioned that the person who provided the initial response has a reputation for providing good, insightful help and has been recognized as a math help leader on multiple websites.
  • #1
rebo1984
18
0
How do I solve this?

Which of the following ordered pairs (x,y) satisfies the system of
inequalities below?
y>-3x+5
y≤ x-2
Choices:
(2,1)
(1,4)
(4,1)
(3,-6)

Please. Thanks.
 
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  • #2
Seriously? Why did you not just put each of the given (x, y) pairs into the expressions and see which ones are correct?
 
  • #3
HallsofIvy makes a good suggestion. After you've done that, look at a plot of the inequalities and the given points to verify your answer:

Click on the points to reveal their coordinates...

[DESMOS=-10,10,-10,10]y\gt-3x+5;y\le x-2;\left(2,1\right),\left(1,4\right),\left(4,1\right),\left(3,-6\right)[/DESMOS]

Look for the one point that falls within both shaded areas simultaneously.
 
  • #4
HallsofIvy said:
Seriously? Why did you not just put each of the given (x, y) pairs into the expressions and see which ones are correct?

There is no need to be rude. I just wanted to know if there was another way of doing it.
 
  • #5
rebo1984 said:
There is no need to be rude.

I see nothing rude about my response.

I just wanted to know if there was another way of doing it.
Then why didn't you ask that question? As you phrased it, you seemed to be saying you had no idea how to do the arithmetic. That was why I said "Seriously?". I did not want to believe that you could NOT do the arithmetic- that would have been rude.
 
  • #6
You are rude. Next time don't respond to any question I post.
 
  • #7
It is a http://mathhelpboards.com/rules/ (No. 11) that when you post a question, you also show what work you've done on the problem so far, and tell where you're stuck. This rule is deep in the ethos of MHB, where we do not hand out solutions, generally, but work with students to get them unstuck. We do this because we believe it is best for the students to do the heavy lifting. They learn more that way. So, when I see an OP like yours, my gut reaction is to reply, "Can you tell us what you've tried, and where you're stuck?"

Was not this partly an excuse for HoI to be uncivil, if he was uncivil (not convinced of that, myself)?
 
  • #8
It was rude and should not be condoned.
 
  • #9
rebo1984 said:
It was rude and should not be condoned.

I can appreciate that you may have felt put off by being asked "Seriously?", but since you didn't provide your thoughts or attempt at the problem, no one had any way of knowing that what you were after was a method besides direct substitution of the given ordered airs into the inequalities. Approaching a student with that question may not be what everyone would do, but I don't think it was meant in a discourteous way, but more as an expression of incredulity. I hope you can see now how your initial post, with no other information given, could evoke such a response. :D

We certainly do not condone rudeness from anyone, as our goal is to provide a friendly atmosphere where people can get math help. I've been doing this (giving math help on various sites) for quite a few years now, and HallsofIvy has been at it at least twice as long as I have. He has always provided good insightful help as long as I've been around, and I haven't seen where he is generally rude or uncivil. He has been recognized as a math help leader on every site on which he and I both participate, which speaks highly for how he is perceived by his math help peers and those to which he provides help. :D
 
  • #10
MarkFL said:
I can appreciate that you may have felt put off by being asked "Seriously?", but since you didn't provide your thoughts or attempt at the problem, no one had any way of knowing that what you were after was a method besides direct substitution of the given ordered airs into the inequalities. Approaching a student with that question may not be what everyone would do, but I don't think it was meant in a discourteous way, but more as an expression of incredulity. I hope you can see now how your initial post, with no other information given, could evoke such a response. :D

We certainly do not condone rudeness from anyone, as our goal is to provide a friendly atmosphere where people can get math help. I've been doing this (giving math help on various sites) for quite a few years now, and HallsofIvy has been at it at least twice as long as I have. He has always provided good insightful help as long as I've been around, and I haven't seen where he is generally rude or uncivil. He has been recognized as a math help leader on every site on which he and I both participate, which speaks highly for how he is perceived by his math help peers and those to which he provides help. :D

That's what I wanted to say. Thank you, MarkFL! And I concur $100\%$.
 

FAQ: Solving system of linear inequalities

1. What are linear inequalities?

Linear inequalities are mathematical expressions that compare two values using the symbols <, >, ≤, or ≥. They represent a range of possible values instead of a single solution.

2. How do you graph linear inequalities?

To graph linear inequalities, you first plot the boundary line using the given inequality symbol (<, >, ≤, or ≥). Then, depending on whether the inequality is > or ≥, you shade the region above or below the line. If the inequality is < or ≤, you shade the region to the left or right of the line. The shaded region represents all possible solutions to the inequality.

3. What is the solution to a system of linear inequalities?

The solution to a system of linear inequalities is the intersection of the solutions to each individual inequality. This can be represented graphically as the overlapping shaded regions on a graph.

4. How do you solve a system of linear inequalities algebraically?

To solve a system of linear inequalities algebraically, you must first solve each inequality for one of the variables. Then, you can use substitution or elimination to find the solution set of the system.

5. What are some real-life applications of solving systems of linear inequalities?

Solving systems of linear inequalities is commonly used in economics, such as in optimizing production and profit in a business. It can also be used in city planning to determine the best location for a new park or road, and in engineering to design structures that can withstand certain weight or force constraints.

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