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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


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?


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I have no idea what this means? – copper.hat Nov 10 '12 at 6:09
@copper.hat - You're right, the description was unclear. I edited the question. I'm sorry . – Billie Nov 10 '12 at 6:15
Looks good to me... – copper.hat Nov 10 '12 at 6:16
@joriki "hidden" mean X - not explicit number. – Billie Nov 10 '12 at 6:18
@joriki - "variable" \ "hidden" = not explicit number. a "sign" (usually X \ Y \ Z etc) that I should find out its value. – Billie Nov 10 '12 at 6:21
up vote 0 down vote accepted

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.

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Thank you so much! – Billie Nov 14 '12 at 20:36

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