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I've got this question:

Find the variable (hidden) in this expression:

$$3X =\begin{bmatrix}0&3\\6&9\end{bmatrix}$$

I've written down that $X$ equals to

$$X=\begin{bmatrix}0&1\\2&3\end{bmatrix}$$

is my answer wrong or right?

I'm not sure if this is the right place, but if it isn't , what is my mistake?

thanks

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    I have no idea what this means?2012-11-10
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    @copper.hat - You're right, the description was unclear. I edited the question. I'm sorry .2012-11-10
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    Looks good to me...2012-11-10
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    @joriki "hidden" mean X - not explicit number.2012-11-10
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    @joriki - "variable" \ "hidden" = not explicit number. a "sign" (usually X \ Y \ Z etc) that I should find out its value.2012-11-10
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    @joriki I'm sorry but I didn't understand the word "qualifying" then I wrote a long answer.2012-11-10
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    OK, I think I understand. Let's delete all these comments so they don't distract from the question.2012-11-10
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    @joriki - Ok, thank you. So my answer is good?2012-11-10
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    Yes. I've never seen this matrix notation with curly braces instead of parentheses before, but other than that the answer is fine.2012-11-10
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    @joriki - I very thank you, both of you. You really helped me - your answers may help me avoid mistakes in the future.2012-11-10
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    For some basic information about writing math at this site see e.g. [here](http://meta.math.stackexchange.com/questions/5020/), [here](http://meta.stackexchange.com/a/70559/155238), [here](http://meta.math.stackexchange.com/questions/1773/) and [here](http://math.stackexchange.com/editing-help#latex).2012-11-10

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Your answer is perfect, no mistake at all. Multiplying/dividing matrices by numbers is so easy: we multiply/divide all the elements in the matrix by that number.