document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=119049>Question 119049</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Goliath is 12 years older than David.In six years, Goliath's age will be twice of David's age. How old is Goliath now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #87186 by </B><A HREF=/tutors/aboutme.mpl?userid=HyperBrain><B>HyperBrain(694)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=HyperBrain><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=87186\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=Goliath's age<BR>\n" );
document.write( "    y=David's age\r<BR>\n" );
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document.write( "IF Goliath is 12 years older than David, THEN:\r<BR>\n" );
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document.write( "x=y+12\r<BR>\n" );
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document.write( "In six yrs, 6 yrs will be added to their present ages so\r<BR>\n" );
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document.write( "Let x+6=the age of Goliath in 6 yrs<BR>\n" );
document.write( "    y+6=the age of David in 6 yrs\r<BR>\n" );
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document.write( "SInce In six years, Goliath's age will be twice of David's age, then,\r<BR>\n" );
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document.write( "x+6=2(y+6)\r<BR>\n" );
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document.write( "But, we know that x=y+12. So,\r<BR>\n" );
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document.write( "(y+12)+6=2(y+6)---substitution<BR>\n" );
document.write( "y+(12+6)=2(y+6)---associative property of addition<BR>\n" );
document.write( "y+18=2(y+6)--------addition of integers<BR>\n" );
document.write( "y+18=2y+2(6)-------distributive property of multiplication over addition<BR>\n" );
document.write( "y+18=2y+12---------multiplication of integers<BR>\n" );
document.write( "2y+12=y+18----------symmetric property of equality<BR>\n" );
document.write( "2y+12-18=y+18-18----subtract 24 to both sides<BR>\n" );
document.write( "2y-6=y+0------------subtraction of integers<BR>\n" );
document.write( "2y-6=y----------------identity property of addition<BR>\n" );
document.write( "2y-6+6=y+6------------add 6 to both sides<BR>\n" );
document.write( "2y+0=y+6------------addition of integers<BR>\n" );
document.write( "2y=y+6--------------identity property of addition<BR>\n" );
document.write( "2y-y=y-y+6----------subtract y to both sides<BR>\n" );
document.write( "y=0+6<BR>\n" );
document.write( "y=6-----------------identity property of addition\r<BR>\n" );
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document.write( "Thus, the age of David is 6.\r<BR>\n" );
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document.write( "Since y=6 and x=y+12, then\r<BR>\n" );
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document.write( "x=6+12---substitution<BR>\n" );
document.write( "x=18\r<BR>\n" );
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document.write( "The age of Goliath is 18.\r<BR>\n" );
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document.write( "The check is left to you.\r<BR>\n" );
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document.write( "Power up,<BR>\n" );
document.write( "HyperBrain!\r<BR>\n" );
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document.write( " </SPAN>\n" );
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