## Simplify: I get y = (10-2x)/5 but book says y = (1/5)(10-2x)

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diaste
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### Simplify: I get y = (10-2x)/5 but book says y = (1/5)(10-2x)

I was wondering what is the correct answer or the simplest form of 2x + 5y=10?
I was asked to solve for y
I answered this: $y=\frac{10-2x}{5}$
The book says $\frac {1}{5}(10-2x)$ is correct. Which is the same though it looks simpler to me.
Wouldn't y = 2-.4x be even simpler?

I hope it displays correctly. It doesn't on the preview.

diaste
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### Re: Simplify

"Ah, now I see!" said the blind man.

$y=\frac15(10-2x)$is what the book says is correct.
I say this is as correct $y=\frac{10-2x}{5}$ but isn't this: y=2-.4x, simpler yet?

I like the decimal form of the answer much better as I'm very used to converting fractions to decimals in my work. To me the decimal is the simplest form and so the book should accept that as a correct answer, well, in my world anyway!

stapel_eliz
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diaste wrote:"Ah, now I see!" said the blind man.

You got it! (I've edited the original post to insert the missing formatting tags.)

diaste wrote:$y=\frac15(10-2x)$is what the book says is correct.
I say this is as correct $y=\frac{10-2x}{5}$

They're exactly the same thing, just arranged a little differently. Since multiplying by one-fifth is the same as dividing by five, either form should be fine.

diaste wrote:but isn't this: y=2-.4x, simpler yet?

Generally, books and teachers prefer the fractional form. But your decimal form should be acceptable since, as you point out, it is the same.

Eliz.

little_dragon
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### Re: Simplify: I get y = (10-2x)/5 but book says y = (1/5)(10-2x)

Sometimes it can be annoying, when you want to write the answer one way but the book has it another way. I haven't figured out what rules or whatever they use to pick which way they do it. You just have to get good at seeing when they're really the same thing.

diaste
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### Re: Simplify: I get y = (10-2x)/5 but book says y = (1/5)(10-2x)

Hey Little Dragon,

I know, isn't that annoying? In Linear equations they want the answer to look like $y=\frac15(10-2x)$ but now that we're graphing, the very next chapter, they want the answer to look like y = 2-.4x. And they didn't say they wanted it in the simpler form. I'm still counting it as a right answer!