Graphing Systems of Inequalities

Genocide

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Feb 11, 2008
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I don't understand how to do any of this math, can someone show me how to arrange everything the right way, and explain how to graph it? I've tried google and everything, its not doing me any good.

y = 2x - 6
x + y = 6

2x - y = 9
6x + 3y = 15

y > 2x - 3
y < 5 - x (this < has a line under it, and yes I know what they mean)

2x + y < 4 (This < has a line under it)
x - y < - 2

-2 < y < 3 (both have lines under them)

1 < x < 4

y < 5 (has a line under it)
y < x + 3

y > 2x (has a line under it)
y > x + 3

y - x > 5 (has a line under it)
y - 2x < 7 (has a line under it)

-5 < x < -1 (both have lines under them)
 

Subhotosh Khan

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Genocide said:
I don't understand how to do any of this math, can someone show me how to arrange everything the right way, and explain how to graph it? I've tried google and everything, its not doing me any good.

y = 2x - 6
x + y = 6

2x - y = 9
6x + 3y = 15

y > 2x - 3
y < 5 - x (this < has a line under it, and yes I know what they mean)

2x + y < 4 (This < has a line under it)
x - y < - 2

-2 < y < 3 (both have lines under them)

1 < x < 4

y < 5 (has a line under it)
y < x + 3

y > 2x (has a line under it)
y > x + 3

y - x > 5 (has a line under it)
y - 2x < 7 (has a line under it)

-5 < x < -1 (both have lines under them)
Assuming you have learned to plot linear equations, for quick review of graphing linear inequalities, go to:

http://www.purplemath.com/modules/ineqgrph.htm

If you are still stuck, write back showing your work and exactly where you are stuck.
 

Genocide

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Feb 11, 2008
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Graphing Linear Inequalities was going to be my next post, all of these problems are giving me a problem. Even the examples. Having problems like x + 2y < -6 is making my life miserable, because none of it makes sense.
 

stapel

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Genocide said:
Graphing Linear Inequalities was going to be my next post, all of these problems are giving me a problem. Even the examples. Having problems like x + 2y < -6 is making my life miserable, because none of it makes sense.
So you're unable to graph the systems of linear inequalities because you haven't learned how to graph single linear inequalities...? Have you learned anything about graphing straight lines...?

Eliz.
 

Genocide

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If u just explain it i'll remember it.
 

stapel

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Genocide said:
If u just explain it i'll remember it.
Unfortunately, we cannot teach courses here, so please study some of the many great lessons available online:

. . . . .Google results for "graphing linear equations"

Once you've learned how to graph straight lines, you can move on to graphing straight lines and then shading one side:

. . . . .Google results for "graphing linear inequalities"

...and then graphing more than one straight line, shading one side of each, and finding the overlap:

. . . . .Google results for "graphing linear inequalities systems"

Give yourself at least an hour or two for each topic, and study at least two lessons from each link. (You may want to split your study over two or more days.) Take the time to work through the examples, rather than just reading them, so the material "sticks" with you. And have fun! :D

Eliz.
 

Genocide

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Feb 11, 2008
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I've figured the inequality stuff out, could you help me with the Solving Quad/Linear Systems Algebraically questions though, those are the only other ones giving me a pain.
 

stapel

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Genocide said:
I've figured the inequality stuff out, could you help me with the Solving Quad/Linear Systems Algebraically questions though, those are the only other ones giving me a pain.
As mentioned previously, we cannot teach courses within this environment. (The reason that solving linear and non-linear systems comprised a chapter or two in your book as that they cannot be covered in a simple forum posting.)

To learn how to solve systems of linear equations by various algebraic methods, try here:

. . . . .Google results for "solving systems linear equations"

. . . . .Google results for "solving systems matrix"

. . . . .Google results for "Cramer's Rule"

To learn how to solve systems of non-linear equations, try here:

. . . . .Google results for "solving systems nonlinear equations"

Eliz.
 
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