Algebra problem->Check if right,pls

**Neenoon** · September 22nd 2008, 12:35 AM

I'm having a hard time learning how to translate a written math problem into algebra equations. Tell me if this is right?

The difference of two number, x and y, is 28. The number y is 8/9 of the number x. Find these 2 numbers.

$x-y = 28$
$8/9 x = y$

$-8(x-y) = -8(28)$
$-8x-8y=-224$

$8/9x=y$
$9(8/9x)=9(y)$
$8x=9y$
$8x-9y=0$

$-8x-8y=-224$
$+8x-9y=0$
$-17y=-224$
$y=224/17$

$x-y=28$
$x-224/17=28$
$x=28+224/17$
$x= 700/17$

$x-y=28$
$700/17-224/17=28$
$28=28$

So what do you guys think?

**Linnus** · September 22nd 2008, 01:07 AM

This part is wrong.

Originally Posted by Neenoon

$-8(x-y) = -8(28)$
$-8x-8y=-224$

it should be $-8x + 8y=-224$

You got the 2 equations right you solve the system wrong. The way you solve the problem is a bit complicated.
Here is how I would do it.

$x-y=28$
$y= \frac {8} {9} x$

so

$x-\frac {8} {9} x=28$
$\frac {1} {9} x=28$
$x= 252$

Plug x into the equation
$252-y=28$
$y=224$

**Neenoon** · September 25th 2008, 12:12 PM

Duh

Let's say I was tired when I did these!

Thanks a whole bunch, 5 points that would have been gone right there!

**saranya** · September 25th 2008, 06:30 PM

Originally Posted by Neenoon

I'm having a hard time learning how to translate a written math problem into algebra equations. Tell me if this is right?

The difference of two number, x and y, is 28. The number y is 8/9 of the number x. Find these 2 numbers.

$x-y = 28$
$8/9 x = y$

$-8(x-y) = -8(28)$
$-8x-8y=-224$

$8/9x=y$
$9(8/9x)=9(y)$
$8x=9y$
$8x-9y=0$

$-8x-8y=-224$
$+8x-9y=0$
$-17y=-224$
$y=224/17$

$x-y=28$
$x-224/17=28$
$x=28+224/17$
$x= 700/17$

$x-y=28$
$700/17-224/17=28$
$28=28$

So what do you guys think?

Hi!
u can get this answer through solve the equation method also

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