document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=309282>Question 309282</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 3x/6 -4/12 =7 ; -36x +24=-504\r<BR>\n" );
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document.write( "In the following pair of equations, both sides of the equation on the left were multifplied by a number to get the equation on the right.  What is the number?\r<BR>\n" );
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document.write( "I know the answer is -72.\r<BR>\n" );
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document.write( "If you could please help me find out how to get that answer that would be so wonderful.  \r<BR>\n" );
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document.write( "Thank you!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #221185 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=221185\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Well a quick and easy way to get a common multiple of 2 (or more) numbers is to simply multiply them. For instance, a common multiple of 17 and 5 is 17*5=85\r<BR>\n" );
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document.write( "In this case, a common multiple between 6 and 12 is 6*12=72. It turns out that the numbers that share the common multiple will go into that common multiple. Ie <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72%2F6=12 ALIGN=MIDDLE  ALT=\"72%2F6=12\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72%2F12=6 ALIGN=MIDDLE  ALT=\"72%2F12=6\"   DISABLED_style= \"max-width:90%; height:auto;\" >. What this means is that you can effectively clear out the denominators of the fractions leaving you with integer terms.\r<BR>\n" );
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document.write( "For instance, multiply 72 by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%2F6 ALIGN=MIDDLE  ALT=\"3x%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72%283x%2F6%29=%2872%2A3x%29%2F6=216x%2F6=36x ALIGN=MIDDLE  ALT=\"72%283x%2F6%29=%2872%2A3x%29%2F6=216x%2F6=36x\"   DISABLED_style= \"max-width:90%; height:auto;\" >. In the given problem, the only difference is that 36x is really -36x. So instead we must multiply both sides by -72.\r<BR>\n" );
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document.write( "Another quick way to realize that -72 is the magic number is to look at the right side. This side already has an integer which will make life easier for us. Take the number 7 and multiply it by some unknown number 'k' to get 7k. This is now equal to the new right side of -504. Set them equal to get 7k=-504. The task now is to solve the equation 7k=-504. Sure enough, solving the equation will get us k=-72 which is the number we're looking for. </SPAN>\n" );
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