document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=881578>Question 881578</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It is given that half the sum of the ages of a father and his son equals the difference between their ages. In 15 years' time, the father will be twice as old as his son. Given that the father is x years old and his son is y years old.<BR>\n" );
document.write( "(a) Form two equations connecting x and y.<BR>\n" );
document.write( "(b) Solve these two simultaneous equations in (a) and find the ages of the father and that of the son.\r<BR>\n" );
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document.write( "My Workings:<BR>\n" );
document.write( "(a) 1/2(x+y)=x-y<BR>\n" );
document.write( "     y+15=2(x+15) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #532453 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=532453\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It is given that half the sum of the ages of a father and his son equals the difference between their ages. In 15 years' time, the father will be twice as old as his son. Given that the father is x years old and his son is y years old.<BR>\n" );
document.write( "(a) Form two equations connecting x and y.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2 ALIGN=MIDDLE  ALT=\"1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >(x+y) = x - y<BR>\n" );
document.write( "x + y = 2(x-y)<BR>\n" );
document.write( "x + y = 2x - 2y<BR>\n" );
document.write( "y + 2y = 2x - x<BR>\n" );
document.write( "3y = x<BR>\n" );
document.write( "and<BR>\n" );
document.write( "x+15 = 2(y+15)<BR>\n" );
document.write( "x + 15 = 2y + 30<BR>\n" );
document.write( "x = 2y + 30 - 15<BR>\n" );
document.write( "x = 2y + 15<BR>\n" );
document.write( ":\r<BR>\n" );
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document.write( "(b) Solve these two simultaneous equations in (a) and find the ages of the father and that of the son.<BR>\n" );
document.write( "Replace x with 3y in the above equation<BR>\n" );
document.write( "3y = 2y + 15<BR>\n" );
document.write( "3y - 2y = 15<BR>\n" );
document.write( " y = 15 yrs is the son's age<BR>\n" );
document.write( "then<BR>\n" );
document.write( "x = 3(15)<BR>\n" );
document.write( "x = 45 yrs is the father's age<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "You can confirm this in the given statements by replacing x and y  </SPAN>\n" );
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