# Matrix is not the same size

I am trying to write this matrix

But this matrix is awful aesthetically. The middle matrix is tall, the other two are short. I want to make all 3 matrixes the same height.

This is my Latex code:

\tt \color{Black}
\begin{bmatrix}
1 & -1 & -1\\
0 & 13 & -10\\
0 & 7 & \phantom{-} 17
\end{bmatrix}

\begin{bmatrix}
I_{1}\\
I_{2}\\
I_{3}
\end{bmatrix}

=

\begin{bmatrix}
\phantom{-}0\\
\phantom{-}4\\
-3
\end{bmatrix}

But this is my problem. I am using macOS Pages that have limited Latex support. This is what apple has to say about it.

Unfortunately this solution is not working.

Is there a way to make everything the same height?

thanks

I looked at the supported commands and it says that \color is supported. This allows one to cheat by putting a white, i.e. invisible, dot on top of the symbols.

\documentclass{article}
\usepackage{amsmath}
\usepackage{color}
\begin{document}
$\begin{bmatrix} \color{white}\dot{\color{black}1} & -1 & -1\phantom{0}\\ \color{white}\dot{\color{black}0} & 13 & -10\\ \color{white}\dot{\color{black}0} & \phantom{-}7 & \phantom{-} 17 \end{bmatrix} % \begin{bmatrix} I_{1}\\ I_{2}\\ I_{3} \end{bmatrix} % = % \begin{bmatrix} \phantom{-}\color{white}\dot{\color{black}0}\\ \phantom{-}\color{white}\dot{\color{black}4}\\ -\color{white}\dot{\color{black}3} \end{bmatrix}$
\end{document}

I Just checked myself, if you remove the %, i.e. insert

$\begin{bmatrix} \color{white}\dot{\color{black}1} & -1 & -1\phantom{0}\\ \color{white}\dot{\color{black}0} & 13 & -10\\ \color{white}\dot{\color{black}0} & \phantom{-}7 & \phantom{-} 17 \end{bmatrix} \begin{bmatrix} I_{1}\\ I_{2}\\ I_{3} \end{bmatrix} = \begin{bmatrix} \phantom{-}\color{white}\dot{\color{black}0}\\ \phantom{-}\color{white}\dot{\color{black}4}\\ -\color{white}\dot{\color{black}3} \end{bmatrix}$

you'll get

(For other Mac users: in a document inside the text, click on the insert symbol, which looks a bit like a reverse double-stroke P, and click insert equation, you'll be able to verify that it works. Whether or not this is an appropriate question for this site, I cannot judge.)

NOTE: I removed the \vphantom parts I had originally as this seems not to be supported by pages.

• In a case like this, rather than a \vphantom, I’d use a \mathstrut (which is itself a \vphantom, namely \vphantom () everywhere.
– GuM
May 25 '18 at 1:26
• Also beware that, in the last matrix, -3 should now be {-3} (the \vphantom inserts an empty box, which is a \mathord). The same remark applies to @mas’ answer too.
– GuM
May 25 '18 at 1:41
• \vphantom is not working for me. Like I said, Pages has a very limited set of Latex. I have tried \phantom and it almost works. The matrices got equal sizes but the alignment is gone.
– Duck
May 25 '18 at 1:55
• There is a minor typo on your code... on the part you type \phantom{-1}7... I think the correct is \phantom{-}7. Adding the 1 shifts the 7 slightly to the right on my Pages. Anyway, your code is fantastic. Thanks.
– Duck
May 26 '18 at 0:17
• Let me ask you something. I have another question about latex on mac, that is how to create a box around a formula. I have searched the whole web and nothing works. Do you by any chance know? If you say yes I will open another question, to let you earn a few points... 😃
– Duck
May 26 '18 at 1:38

In addition to marmot's answer, you can use mathtools to right justify the numbers:

\documentclass{article}
\usepackage{mathtools}
\begin{document}
$\begin{bmatrix*}[r] \vphantom{I_{1}}1 & -1 & -1\\ \vphantom{I_{1}}0 & 13 & -10\\ \vphantom{I_{1}}0 & 7 & 17 \end{bmatrix*} % \begin{bmatrix} I_{1}\\ I_{2}\\ I_{3} \end{bmatrix} % = % \begin{bmatrix*}[r] \vphantom{I_{1}} 0\\ \vphantom{I_{1}} 4\\ \vphantom{I_{1}}-3 \end{bmatrix*}$
\end{document}

• \vphantom is not working for me. Like I said, Pages has a very limited set of Latex. I have tried \phantom and it almost works. The matrices got equal sizes but the alignment is gone. BTW that is the meaning of having bmatrix and bmatrix*?
– Duck
May 25 '18 at 1:55