Hi!

Could someone please solve this equation for me and try to explain how you did that. 4*(x-1)^2+1/3=7/9

I do know the answer for this equation. But I don't know how to think when solving it and how to get the answer.

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- Sep 2nd 2011, 05:06 AMjimuttI need help with a 2nd grade equations
Hi!

Could someone please solve this equation for me and try to explain how you did that. 4*(x-1)^2+1/3=7/9

I do know the answer for this equation. But I don't know how to think when solving it and how to get the answer. - Sep 2nd 2011, 05:23 AMskeeterRe: I need help with a 2nd grade equations
$\displaystyle 4(x-1)^2 + \frac{1}{3} = \frac{7}{9}$

multiply every term by 9 to clear the fractions ...

$\displaystyle 36(x-1)^2 + 3 = 7$

subtract 3 from both sides ...

$\displaystyle 36(x-1)^2 = 4$

divide both sides by 36 and reduce ...

$\displaystyle (x-1)^2 = \frac{1}{9}$

"un"square both sides ...

$\displaystyle x-1 = \pm \frac{1}{3}$

add 1 to both sides ...

$\displaystyle x = 1 \pm \frac{1}{3}$

so, the two solutions are $\displaystyle x = \frac{4}{3}$ and $\displaystyle x = \frac{2}{3}$ - Sep 2nd 2011, 05:45 AMHallsofIvyRe: I need help with a 2nd grade equations
This is a

**second grade**problem? Seven year olds are expected to be able to do this? - Sep 2nd 2011, 05:54 AMjimuttRe: I need help with a 2nd grade equations
Thank you very much skeeter!

Never realised that it was so easy.

HallsofIvy: Well, not really :P I just translated the name we use for this kind of equations here in Sweden directly to english. So It maybe isn't very correct ;) - Sep 2nd 2011, 06:05 AMskeeterRe: I need help with a 2nd grade equations
check this out ...

http://http://www.wired.com/magazine/2011/07/ff_khan/all/1

... won't be long until we're all out of a job. - Sep 2nd 2011, 06:27 AMjimuttRe: I need help with a 2nd grade equations
Okey, here you've got one more equation to help me out with. I have to say that this book really sucks at explaining (and so does my math teacher also, sadly enough).

2x^2+4x+40=3x^2-2x

And by the way. It would be extreamly nice if you could help me out two factorizing problems also:

1. 2x+2a2b(x+a)

2. a^(x+2)-a^(2x) - Sep 2nd 2011, 07:45 AMSironRe: I need help with a 2nd grade equations
Put all the terms to one side, so you get:

$\displaystyle 2x^2+4x+40-3x^2+2x=0$

$\displaystyle \Leftrightarrow -x^2+6x+40=0$

Use the quadratic formula to continue.

Ex 2:

Determine which factor the terms have in common, for example:

2. $\displaystyle a^{x+2}-a^{2x}=a^{x}\cdot a^{2} - (a^{x})^2=...$ - Sep 2nd 2011, 02:16 PMskeeterRe: I need help with a 2nd grade equations