View source for Documentation/FAQ/Formula/How do I align my equations at the equality sign?

{{DISPLAYTITLE: How do I align my equations at the equality sign?}}

<section begin=question/>
'''How do I align my equations at the equality sign?'''
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<section begin=answer/>
Currently ''Math'' does not have an alignment construction (track [http://www.openoffice.org/issues/show_bug.cgi?id=5998 here]).
Instead you can use a matrix.

For example to typeset the equation
[[Image:005a.gif]]

you should enter the following:
<pre>
matrix{
   alignr x+y # {}={} # alignl 2 ##
   alignr x   # {}={} # alignl 2-y
}
</pre>
The empty braces around = are necessary because = is a binary
operator and thus needs an expression on each side.

You can reduce the spacing around = if you change the inter-column
spacing of the matrix:

#Select '''Format-Spacing'''
#Click '''Category''' and choose '''Matrices''' in the pop-up menu.
#Now enter<font color="brown">''' 0% '''</font>under '''Column spacing''' and click '''OK'''.


Here is another example using a different solution:

To typeset the equation

[[Image:005b.gif]]

the trick is to use <font color="brown">'''phantom'''</font> as follows:

<pre>&quot;&quot;3(x+4)-2(x-1)=3 x+12-(2 x-2) newline
&quot;&quot;phantom {3(x+4)-2(x-1)}=3 x+12-2 x+2 newline
&quot;&quot;phantom {3(x+4)-2(x-1)}=x+14</pre>

<P STYLE="margin-top: 0.2cm; margin-bottom: 0.21cm; font-weight: medium">
The effect of the empty quotation marks is to left justify the line -
a line starting with text (even an empty text) will always be left
justified.</P>

You can replace<font color="brown">''' &quot;&quot; '''</font>with <font color="brown">'''alignl'''</font>.

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[[Category:Documentation/FAQ/Formula]]