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#226 2011-08-06 02:37:24
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
number 6 was the graph one
(x-(-3))(x-(-4))=(x+3)(x+4)
(x+3)(x+4)=x^2+7x+12
-4,-1
Last edited by zee-f (2011-08-06 02:38:12)
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#227 2011-08-06 02:38:56
- bobbym
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Re: Solving Quadratics by Factoring and Graphing
( x + 3 ) = 0
Subtract 3 from both sides.
x = - 3
( x + 4 ) = 0
Subtract 4 from both sides.
x = - 4
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#228 2011-08-06 02:42:21
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
yeah i missed that one
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#229 2011-08-06 02:44:11
- bobbym
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Re: Solving Quadratics by Factoring and Graphing
No problem, do you see it now?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#230 2011-08-06 02:45:21
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
yeah i did i like the graph method its much easier
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#231 2011-08-06 02:47:12
- bobbym
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Re: Solving Quadratics by Factoring and Graphing
Of course it is! Especially for book problems. The great Forman S. Acton says always graph the function!
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#232 2011-08-06 02:49:22
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
#2- 3x^3-12x=0
3x(-4+x^2)=0
3x((2+x)(-2+x))=0
x=0 2+x=0
2+-2+x=0+-2
2+-2=0
0+x=0+-2
x=0+-2
0+-2=-2
x=-2
-2+x=0
x=0
ok for this one i was really clear with her and she said
How did you solve -2 + x = 0.
Add '2' to each side of the equation.
-2 + 2 + x = 0 + 2
-2 + 2 = 0
0 + x = 0 + 2
x = 0 + 2
0 + 2 = 2
x = 2
this is what the new answer should be
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#233 2011-08-06 02:52:40
- bobbym
- bumpkin
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Re: Solving Quadratics by Factoring and Graphing
Hi;
Yes, you should end up with (2, 0, -2)
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#234 2011-08-06 06:17:18
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
i need help on this one please i posted this to my teacher
(x+1\2)(x-4)=x^2-7/2-2
she said
12. Good. When we have a problem that contains a fraction, we will multiply the equation by the denominator to remove the fraction. Try this please.
so do i multiply 1/2 by 4 ?
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#235 2011-08-06 06:50:45
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
need help on this one please i posted this to my teacher
(x+1\2)(x-4)=x^2-7/2-2
she said
12. Good. When we have a problem that contains a fraction, we will multiply the equation by the denominator to remove the fraction. Try this please.
so do i multiply 1/2 by 4 ?
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#236 2011-08-06 08:10:41
- anonimnystefy
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Re: Solving Quadratics by Factoring and Graphing
no you multyply everything by 2.
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#237 2011-08-06 08:30:45
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
(x+1)(x-8)=0
(x^2-7-8)
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#238 2011-08-06 12:33:23
- bobbym
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Re: Solving Quadratics by Factoring and Graphing
Hi zee-f;
Was this the problem?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#239 2011-08-07 01:29:45
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
nope the 7/2 is subtracted by 2 not added
(x+1\2)(x-4)=x^2-7/2-2
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#240 2011-08-07 01:35:01
- bobbym
- bumpkin
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Re: Solving Quadratics by Factoring and Graphing
Hi;
Like this?
Are you sure that does not have an x after the 7 / 2 ?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#241 2011-08-07 02:25:53
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
the original question says Work backwards to write a quadratic equation that will have solutions of x = -1/2 and x = 4.
my solution was x^2-7/2-2
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#242 2011-08-07 02:26:58
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
i multiplied by 2 and got
(x+1)(x-8)=0
(x^2-7-8)
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#243 2011-08-07 02:27:28
- bobbym
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Re: Solving Quadratics by Factoring and Graphing
Hi zee-f;
That is not correct.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#244 2011-08-07 02:38:38
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
the way i multiplied or the whole thing ?
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#245 2011-08-07 02:40:11
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
this is what i posted and this is my teachers reply
12. (x+1\2)(x-4)=x^2-7/2-2)
12. Good. When we have a problem that contains a fraction, we will multiply the equation by the denominator to remove the fraction. Try this please.
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#246 2011-08-07 02:43:45
- bobbym
- bumpkin
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- Registered: 2009-04-12
- Posts: 109,606
Re: Solving Quadratics by Factoring and Graphing
Hi;
Your teacher is incorrect.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#247 2011-08-07 03:28:41
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
the thing is she doesn't want it in fraction form
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#248 2011-08-07 03:35:01
- bobbym
- bumpkin
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Re: Solving Quadratics by Factoring and Graphing
Yes but what about the x after the 7 / 2? it is missing in her answer!
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#249 2011-08-07 05:15:31
- zee-f
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Re: Solving Quadratics by Factoring and Graphing
how do i switch it ?
One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3
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#250 2011-08-07 05:23:22
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Solving Quadratics by Factoring and Graphing
Hi;
Switch what?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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