document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171037>Question 171037</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You are 4 years older than your brother. Two years ago you were 1.5 x older than him. How old are you know? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #126250 by </B><A HREF=/tutors/aboutme.mpl?userid=gonzo><B>gonzo(654)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=gonzo><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=126250\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let your age be x.<BR>\n" );
document.write( "let your brother's age be y.<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "you are now 4 years older than your brother:<BR>\n" );
document.write( "x = y + 4<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "two years ago you were 1.5 times older than your brother:<BR>\n" );
document.write( "x - 2 = 1.5 * y<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "how old are you now?<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "you have 2 equations that need to be solved simultaneously (the same values for x and y make both equations true).<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "one way to solve this is as follows:<BR>\n" );
document.write( "leave your first equation as it is:<BR>\n" );
document.write( "x = y + 4<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "take your second equation and add 2 to both sides:<BR>\n" );
document.write( "x = 1.5*y + 2<BR>\n" );
document.write( "----<BR>\n" );
document.write( "since both equations equal to x, then both equation equal to each other:<BR>\n" );
document.write( "y + 4 = 1.5*y + 2<BR>\n" );
document.write( "solve for y:<BR>\n" );
document.write( "subtract 2 from both sides of the equation:<BR>\n" );
document.write( "y + 4 - 2 = 1.5*y + 2 - 2<BR>\n" );
document.write( "simplify:<BR>\n" );
document.write( "y + 2 = 1.5 * y<BR>\n" );
document.write( "subtract y from both sides of the equation:<BR>\n" );
document.write( "y - y + 2 = 1.5 * y - y<BR>\n" );
document.write( "simplify:<BR>\n" );
document.write( "2 = .5 * y<BR>\n" );
document.write( "multiply both sides of equation by 2:<BR>\n" );
document.write( "2 * 2 = 2 * .5 * y<BR>\n" );
document.write( "simplify:<BR>\n" );
document.write( "4 = y<BR>\n" );
document.write( "exchange sides of equation (value remains the same):<BR>\n" );
document.write( "y = 4<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "you now have y = 4.<BR>\n" );
document.write( "take either equation and solve for x:<BR>\n" );
document.write( "take:<BR>\n" );
document.write( "x = y + 4<BR>\n" );
document.write( "substitute 4 for y:<BR>\n" );
document.write( "x = 4 + 4 = 8<BR>\n" );
document.write( "you now have:<BR>\n" );
document.write( "x = 8<BR>\n" );
document.write( "y = 4<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "the first equation is satisfied since you used it to find x.<BR>\n" );
document.write( "take the second equation and substitute 4 for y and 8 for x:<BR>\n" );
document.write( "x - 2 = 1.5 * y<BR>\n" );
document.write( "substitute for x and y:<BR>\n" );
document.write( "8 - 2 = 1.5 * 4<BR>\n" );
document.write( "simplify:<BR>\n" );
document.write( "6 = 1.5 * 4<BR>\n" );
document.write( "6 = 6<BR>\n" );
document.write( "equation is true.<BR>\n" );
document.write( "you are 8 years old now (x = 8).<BR>\n" );
document.write( "your brother is 4 years old now (y = 4).<BR>\n" );
document.write( "-----<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );