Scratch

JJROCKER · 2011-06-13 00:16:09

Correct! Nice Job!

bbbeb · 2011-06-13 00:16:55

Harakou wrote:
bbbeb wrote:
3x^2 + 6x + 6 = 0 Not possible I believe, got stuck on (6 (+ or -) sqrt (-36) )/ 6
Nope, it's possible, but the answer is a complex number.

AKA a number with i?

I know.
A real number is what I meant.

5^2^2

5^4

625

JJROCKER · 2011-06-13 00:23:06

Yeah correct

AtomicBawm3 · 2011-06-13 09:33:41

Ok, I'm not sure if I saw this, but here's what Kaybee thought he/she was doing, but why it was wrong.

The answer is in fact 2. (2+1)(2+1)=9 If you used 8, you would wind up at 81.

What Kaybee did is use the idea supposed to be used when the equation is set to 0 (this usually happens with quadratic equations). For example:

(x-3)(x+5)=0

Because the answer is zero, you know that one of the multiplied values must be 0, thus:

x-3=0 or x+5=0

resulting in:

x=3 or x=-5 either answer will work.

Now to give you guys something hard:

simplify: y(x-(y-x) )+(y-x)^2

The answer is something interesting, and once it is found be you guys, I'll explain why this specific equation can be helpful.

mathematics · 2011-06-13 10:05:13

y (x - (y - x)) + (y - x)^2 = y (x - y + x) + y^2 - 2 y x + x^2 = y x - y^2 + y x + y^2 - 2 y x + x^2 = x^2

If anyone is interested, try this:
If f(x) = x^4 + m x^2 + 4 x + n is divisible by (x - 1)^2, find the value of 2 m + 3 n.

Last edited by mathematics (2011-06-13 10:10:27)

AtomicBawm3 · 2011-06-13 10:15:04

mathematics wrote:
y (x - (y - x)) + (y - x)^2 = y (x - y + x) + y^2 - 2 y x + x^2 = y x - y^2 + y x + y^2 - 2 y x + x^2 = x^2

Yep. Good job!

This is helpful for squaring numbers in your head. For example:
I can't do 787^2 in my head, but I can do:
800(774)+13^2=8*77400+169
4*154800+169
309600*2+169
619369

See? Very helpful...Now I just have to check that that's right...
619369, yep, got it right.

Earthboundjeff · 2011-06-13 10:39:30

I'm in algebra right now!

Last edited by Earthboundjeff (2011-06-13 10:40:19)

JJROCKER · 2011-06-13 19:00:38

Earthboundjeff wrote:
I'm in algebra right now!

So are lots of other people on scratch

JJROCKER · 2011-06-13 23:34:05

Can anybody else give me more questions to put up?

JJROCKER · 2011-06-15 21:28:32

Update Schedule:
Tomorrow
Friday
Saturday
Sunday

16Skittles · 2011-06-16 08:38:05

JJROCKER wrote:
Talk about anything Algebra.
Highlight for answers
Questions of the day:
8^2+64
2^2^2=8
8! 8*7*6*5*4*3*2=40320
(2x-3)(4x+2)+8x^2+4x-12X-6
(x+1)(x+1)=9 (x+1)^2=9 x+1=3 x=2
3x^2 + 6x + 6 = 0 X=1/4
Give an example of a factorial expression. 5!
5^2^2=125

I believe this is correct. IDK if anyone's answered this yet, so I put it in gray.
I'm two grades ahead in math! I had algebra I last year and will have Geometry this year. big_smile

Last edited by 16Skittles (2011-06-16 08:39:06)

JJROCKER · 2011-06-16 19:30:19

wow awesome. Great job!

jji7skyline · 2011-06-16 19:37:36

8^2 = 16

2^2^2 = 8
8! = 1+2+3+4+5+6+7+8 = 36

(2x-3)(4x+2) = 0 ???

(x+1)(x+1)=9 ???

3x^2 + 6x + 6 = 0 ???

What is an equation? An expression with the equal sign and the answer for example 5+5=10

What is an expression? A number question without the answer for example 5+5

Give an example of a factorial expression. ???

5^2^2 =20

I've just started learning algebra so yea...

JJROCKER · 2011-06-16 19:39:18

And there goes all my questions. Can you come up with some new ones?

jji7skyline · 2011-06-16 19:53:37

JJROCKER wrote:
And there goes all my questions. Can you come up with some new ones?

y
-----------------------------------
| |
| | x
| |
_______________________

Find x...

Found it!

JJROCKER · 2011-06-16 19:56:46

no seriously

jji7skyline · 2011-06-16 19:58:57

JJROCKER wrote:
no seriously

I've got a Yr8 (Thats Yr7 for non-queenslanders cuz we go to school one year early) textbook next to me... will that do?

JJROCKER · 2011-06-16 20:01:26

whatever you want

jji7skyline · 2011-06-16 20:04:57

1. Daniel and Travis are twins, but their sister Phillipa is 3 years older. If the sum of their 3 ages is 36 how old are the twins? - please supply answer along with a formula

2. A bicycle rental store charges a flat fee of $15 plus $5 a day to rent a mountain bike

(a) If x is the number of days a mountain bike is rented, write and equation to show the cost of renting a mountain bike (gimme a formula)

(b) If a person was charged $85 for renting a mountain bike, for how many days did the person rent the bike?

Try those neutral <--poker face

JJROCKER · 2011-06-16 20:07:14

ok thanks, ill try

AtomicBawm3 · 2011-06-16 20:47:33

jji7skyline wrote:
8^2 = 16 wrong... =64

2^2^2 = 8 wrong... =16 or 2^4
8! = 1+2+3+4+5+6+7+8 = 36 wrong... 1*2*3*4*5*6*7*8 = 40320

(2x-3)(4x+2) = 0 ??? x=1.5 or x=-.5

(x+1)(x+1)=9 ??? x=2

3x^2 + 6x + 6 = 0 ??? x=1+/-2i

What is an equation? An expression with the equal sign and the answer for example 5+5=10

What is an expression? A number question without the answer for example 5+5

Give an example of a factorial expression. ???

5^2^2 =20 wrong...=5^4 = 625

I've just started learning algebra so yea...

AtomicBawm3 · 2011-06-16 20:51:05

jji7skyline wrote:
1. Daniel and Travis are twins, but their sister Phillipa is 3 years older. If the sum of their 3 ages is 36 how old are the twins? - please supply answer along with a formula

2. A bicycle rental store charges a flat fee of $15 plus $5 a day to rent a mountain bike

(a) If x is the number of days a mountain bike is rented, write and equation to show the cost of renting a mountain bike (gimme a formula)

(b) If a person was charged $85 for renting a mountain bike, for how many days did the person rent the bike?

Try those <--poker face

1) 3x+3=36
x=11
The twins are 11 years old

a) c=5x+15 where c is the total cost
b) 85=5x+15
5x=70
x=14
The person rented the bike for 2 weeks.

JJROCKER · 2011-06-16 20:54:52

Thanks everyone for the questions

mathematics · 2011-06-17 02:55:06

mathematics wrote:
If anyone is interested, try this:
If f(x) = x^4 + m x^2 + 4 x + n is divisible by (x - 1)^2, find the value of 2 m + 3 n.

throughthefire · 2011-06-17 12:04:37

3x^2 + 6x + 6 = 0
no solution!

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#51 2011-06-13 00:16:09

Re: Official Algebra Topic

#52 2011-06-13 00:16:55

Re: Official Algebra Topic

Harakou wrote:

bbbeb wrote:

#53 2011-06-13 00:23:06

Re: Official Algebra Topic

#54 2011-06-13 09:33:41

Re: Official Algebra Topic

#55 2011-06-13 10:05:13

Re: Official Algebra Topic

#56 2011-06-13 10:15:04

Re: Official Algebra Topic

mathematics wrote:

#57 2011-06-13 10:39:30

Re: Official Algebra Topic

#58 2011-06-13 19:00:38

Re: Official Algebra Topic

Earthboundjeff wrote:

#59 2011-06-13 23:34:05

Re: Official Algebra Topic

#60 2011-06-15 21:28:32

Re: Official Algebra Topic

#61 2011-06-16 08:38:05

Re: Official Algebra Topic

JJROCKER wrote:

#62 2011-06-16 19:30:19

Re: Official Algebra Topic

#63 2011-06-16 19:37:36

Re: Official Algebra Topic

#64 2011-06-16 19:39:18

Re: Official Algebra Topic

#65 2011-06-16 19:53:37

Re: Official Algebra Topic

JJROCKER wrote:

#66 2011-06-16 19:56:46

Re: Official Algebra Topic

#67 2011-06-16 19:58:57

Re: Official Algebra Topic

JJROCKER wrote:

#68 2011-06-16 20:01:26

Re: Official Algebra Topic

#69 2011-06-16 20:04:57

Re: Official Algebra Topic

#70 2011-06-16 20:07:14

Re: Official Algebra Topic

#71 2011-06-16 20:47:33

Re: Official Algebra Topic

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#72 2011-06-16 20:51:05

Re: Official Algebra Topic

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#73 2011-06-16 20:54:52

Re: Official Algebra Topic

#74 2011-06-17 02:55:06

Re: Official Algebra Topic

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#75 2011-06-17 12:04:37

Re: Official Algebra Topic

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