<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div apple-content-edited="true"><div><div>On Jan 4, 2009, at 23:30, Sebastian Canagaratna wrote:</div></div></div><div><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; ">\begin{align*}<br> 4x+ 6y -2z &= -4\\<br> x -y +2z &= 9\\[-0.2in]<span class="Apple-converted-space"> </span><br>\underline{\phantom{4x+6y-2z}}&\underline{\phantom{y}}\underline{\phantom{-4y}}\\<br> 5x + 5y &= 5\\<br> x + y &= 1<br>\end{align*}<br>I have used underline and for alignment, instead of using \phantom{=} it<span class="Apple-converted-space"> </span><br>is necessary to use \phantom{y} otherwise the lines don't algin<span class="Apple-converted-space"> </span><br>horizontally. Similarly the added y in -4y.</span></blockquote><br></div><div>Thanks! I'm sure your two suggestions will be useful to me. I tried the following alternative which also worked. What I found was the = in the RHS \phantom was not a problem, rather the absence of a y. If there's something hanging down on the left, there needs to be something hanging down on the right.</div><div><br></div><div><div><font class="Apple-style-span" face="Monaco">\begin{align*}</font></div><div><font class="Apple-style-span" face="Monaco"> 4x +6y -2z &= -4 \\</font></div><div><font class="Apple-style-span" face="Monaco"> x -y +2z &= 9 \\[-12pt] </font></div><div><font class="Apple-style-span" face="Monaco">\underline{\phantom{4x+6y-2z}}&\underline{\phantom{= -4y}}\\</font></div><div><font class="Apple-style-span" face="Monaco"> 5x + 5y &= 5 \\</font></div><div><font class="Apple-style-span" face="Monaco"> x + y &= 1</font></div><div><font class="Apple-style-span" face="Monaco">\end{align*}</font></div></div><div><br></div><div>Geoffrey</div><div>--</div><div>Geoffrey S. Knauth | <a href="http://knauth.org/gsk">http://knauth.org/gsk</a></div><br></body></html>