document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=919202>Question 919202</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 3^a-b= 27 and 3^a+b=243  what is the value of a?  I have the answer a-b=3 and a+b=5 and if you add the equations together 2a=8 so a =4 but don't understand why.   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #557546 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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/cgi-bin/show-face.mpl?user=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=557546\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a-b = 3 because 3^3 = 27, and the exponential function is 1-to-1.\r<BR>\n" );
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document.write( "Similarly a+b = 5 since 3^5 = 243.\r<BR>\n" );
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document.write( "Once you have a-b = 3, a+b = 5, you can solve for a and b. </SPAN>\n" );
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