document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162173>Question 1162173</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Marcus's father is 49 years old currently. If Marcus's father's is 4 years older than 3 times Marcus's age, how old is Marcus now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #785895 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=785895\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Informally....<br><BR>\n" );
document.write( "Take away the \"extra\" 4 years and Marcus's father will be 45 instead of 49.<br><BR>\n" );
document.write( "Then divide that by 3 to find that Marcus's age is 15.<br><BR>\n" );
document.write( "Formally....<br><BR>\n" );
document.write( "x = Marcus's age<BR>\n" );
document.write( "3x+4 = father's age<br><BR>\n" );
document.write( "His father's age is 4 more than 3 times Marcus's:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x%2B4+=+49 ALIGN=MIDDLE  ALT=\"3x%2B4+=+49\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3x+=+45 ALIGN=MIDDLE  ALT=\"3x+=+45\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+15 ALIGN=MIDDLE  ALT=\"x+=+15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWER: Marcus is 15.<br><BR>\n" );
document.write( "For the second part....<br><BR>\n" );
document.write( "Since Marcus is now 15 and his father is 49, his father's age was 49-15 = 34 when Marcus was born.<br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );