document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=147760>Question 147760</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1. The sum of the ages of two friends is 60. if three times the age of one friend is 9 less than four times the age of the other, how old is each?\r<BR>\n" );
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document.write( "2. Rolly is twice as old as his brother, Darwin. In five years, Darwin will be the same age as his brother ten years ago. What are their present ages? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #108136 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=108136\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. The sum of the ages of two friends is 60.<BR>\n" );
document.write( "x + y = 60<BR>\n" );
document.write( "y = (60-x)<BR>\n" );
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document.write( "three times the age of one friend is 9 less than four times the age of the other,<BR>\n" );
document.write( "3x = 4y - 9<BR>\n" );
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document.write( "how old is each?<BR>\n" );
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document.write( "Substitute (60-x) for y in the above equation:<BR>\n" );
document.write( "3x = 4(60-x) - 9<BR>\n" );
document.write( "3x = 240 - 4x - 9<BR>\n" );
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document.write( "3x + 4x = 240 - 9<BR>\n" );
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document.write( "7x = 231<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=231%2F7 ALIGN=MIDDLE  ALT=\"231%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 33 yrs old<BR>\n" );
document.write( "then<BR>\n" );
document.write( "60 - 33 = 27 yrs old<BR>\n" );
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document.write( "Check solution in the statement:<BR>\n" );
document.write( "three times the age of one friend is 9 less than four times the age of the other,<BR>\n" );
document.write( "3(33) = 4(27) - 9<BR>\n" );
document.write( "99 = 108 - 9<BR>\n" );
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document.write( "2. Rolly is twice as old as his brother, Darwin. <BR>\n" );
document.write( "r = 2d<BR>\n" );
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document.write( "In five years, Darwin will be the same age as his brother ten years ago.<BR>\n" );
document.write( "d + 5 = r - 10<BR>\n" );
document.write( "d = r - 10 - 5<BR>\n" );
document.write( "d = r - 15<BR>\n" );
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document.write( " What are their present ages?<BR>\n" );
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document.write( "Substitute 2d for r in the above equation<BR>\n" );
document.write( "d = 2d - 15<BR>\n" );
document.write( "d - 2d = -15<BR>\n" );
document.write( "-d = -15<BR>\n" );
document.write( "d = 15 yrs is Darwin's present age <BR>\n" );
document.write( "then<BR>\n" );
document.write( "2(15) = 30 yrs is Roll's present age<BR>\n" );
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document.write( "Check solution in statement:<BR>\n" );
document.write( "In five years, Darwin will be the same age as his brother ten years ago.<BR>\n" );
document.write( "15 + 5 = 30 - 10 </SPAN>\n" );
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