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#76 2011-08-22 07:48:03
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Hi;
Look at post #74 for a sec. When you expand (x+3)(x+3) you do not get x^2 + 9
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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#77 2011-08-22 08:16:49
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
That is true. But when you expand the expression you should get what you factored back.
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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#78 2011-08-22 08:20:17
- zee-f
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- Registered: 2011-05-12
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Re: review
so i cant factor it because its the sum of squares right ?
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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#79 2011-08-22 08:51:06
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
True, it will not factor using any of the methods you know.
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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#80 2011-08-22 09:08:31
- zee-f
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Re: review
hey bobby and is the rest of my work correct
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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#81 2011-08-22 09:19:17
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Looking at the next one, hold on.
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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#82 2011-08-22 09:24:33
- zee-f
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- Posts: 1,220
Re: review
i doubled checked if it works it did give me 0
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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#83 2011-08-22 09:27:43
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
16) Is correct!
Please bring the rest down here.
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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#84 2011-08-22 09:36:58
- zee-f
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- Registered: 2011-05-12
- Posts: 1,220
Re: review
17. Solve x^2 - x = 56
x^2-x=56
-56+-1x+x^2=0
(-7+-1x)(8+-1x)=0
-7+-1x=0+7
-7+-1x
-1x=7
X=-7
8+-1x=0
-1x=0-8
-1x=-8
X=8
X=-7,8
18- roots are -1,1
(x+1)(x-1)=
x^2-x-1
19. The product of two consecutive positive integers is 42. Write and solve a quadratic equation to find the numbers.
19- x^2+x=42
0=x^2+x-42
42-x+x^2=0
(x+7)(x-6)=0
X=6
Or -7
x=6
x+1=7 so x=6 and 7
20. A cannon ball is shot from a cannon on top of a hill that is 73.5 meters above sea level. The cannon ball leaves the cannon with a velocity of 9.8 m/s. Write and solve a quadratic equation to determine when the cannon ball will reach sea level.
20-
0 = -4.9t² + 9.8t + 73.5
0 = -4.9(t² - 2t - 15)
0 = -4.9(t - 5)(t + 3)
t - 5 = 0 and t + 3 = 0
t = {5,-3}
t = 5 since t = -3 is not acceptable negative value.
the cannon ball will reach sea level at 5 seconds.
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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#85 2011-08-22 09:38:05
- zee-f
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Re: review
for #18 i uploaded the image earlier
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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#86 2011-08-22 09:41:11
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
17) Is correct!
18) 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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#87 2011-08-22 09:44:34
- zee-f
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Re: review
from the picture the root are -1,1
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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#88 2011-08-22 09:47:56
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Yes, but that is not the correct equation for that graph!
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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#89 2011-08-22 09:48:23
- zee-f
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- Registered: 2011-05-12
- Posts: 1,220
Re: review
what did i do wrong? is it this part ?x^2-x-1
Last edited by zee-f (2011-08-22 09:49:29)
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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#90 2011-08-22 09:53:22
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Exact a mundo! You multiplied wrong.
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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#91 2011-08-22 09:55:15
- zee-f
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- Registered: 2011-05-12
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Re: review
so is (x^2-1x-1) correct ?
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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#92 2011-08-22 09:57:36
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Nope. The middle term would cancel. Please try it again.
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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#93 2011-08-22 10:03:35
- zee-f
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Re: review
ok so (x+1)(x-1)
x*x=x^2
x*-1=-1x
1*x=1x
1*-1=-1
(x^2-1x+1x-1)
(x^2-1)
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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#94 2011-08-22 10:09:30
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Hi;
That is 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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#95 2011-08-23 06:57:26
- zee-f
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Re: review
i got all the rest correct to except this one
10.
Divide (3x 2)(x - 4) (x - 4)(6 5x) / (4 x)(8x 1)
10-
(3x-2)(x-4)-(x-4)(6-5x)/(4-x)(8x-1)
The (x-4) cancels out because the (x-4)is common in all the terms of the top and bottom
[(3x-2)]-[(6-5x)]/-(8x-1)
3x+5x=8x
-2-(-6)=-8
8x-8/-(8x-1)
8x-8 factored = 8(x-1)
8(x-1)/-(8x-1) = -1+7/8x-1
this what i got for the reply#10. This looks good up to 8(x-1)/-(8x - 1). After that you lost me.
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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#96 2011-08-23 07:26:02
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Hi;
This one has already been done.
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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#97 2011-08-23 08:09:00
- zee-f
- Member
- Registered: 2011-05-12
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Re: review
(3x-2)-(6-5x)/-(8x-1)=
(8x-8/-8x+1)= -1 with a remainder of -7
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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#98 2011-08-23 08:17:49
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Hi;
That is not quite 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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#99 2011-08-23 08:32:09
- zee-f
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- Registered: 2011-05-12
- Posts: 1,220
Re: review
8(x-1)
factored its going to give me
8x-8
so 8x-1/8x-8
am going to get 1 with a remainder of -7
so 1+-7/8x-1
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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#100 2011-08-23 08:39:39
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: review
Nope. The answer is -1 with a 7 remainder.
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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