document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=664371>Question 664371</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There are 15 total bicycles and tricycles and there is a total of 37 wheels. How many tricycles are there? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #413288 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=413288\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> total of 15 bicycles and tricycles<BR>\n" );
document.write( "total of 37 wheels.<BR>\n" );
document.write( "how many tricycles?\r<BR>\n" );
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document.write( "let x = number of bicycles<BR>\n" );
document.write( "let y = number of tricycles\r<BR>\n" );
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document.write( "x + y = 15 (number of bicycles + number of tricycles = 15)<BR>\n" );
document.write( "2x + 3y = 37 (number of bicycle wheels + number of tricycle wheels = 37)\r<BR>\n" );
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document.write( "you need to solve these 2 equations simultaneously.<BR>\n" );
document.write( "use one of the equations to solve for y<BR>\n" );
document.write( "use that value of for y to replace y in the second equation.\r<BR>\n" );
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document.write( "we'll solve for y in the equation of x + y = 15 because it's easier to do.<BR>\n" );
document.write( "start with x + y = 15<BR>\n" );
document.write( "subtract x from both sides of the equation to get y = 15 - x\r<BR>\n" );
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document.write( "replace y with 15 - x in the second equation.<BR>\n" );
document.write( "second equation is 2x + 3y = 37<BR>\n" );
document.write( "replace y with 15 - x to get 2x + 3 * (15 - x) = 37<BR>\n" );
document.write( "simplify to get 2x + 45 - 3x = 37<BR>\n" );
document.write( "combine like terms to get -x + 45 = 37<BR>\n" );
document.write( "subtract 45 from both sides of the equation to get -x = 37 - 45<BR>\n" );
document.write( "simplify to get -x = -8<BR>\n" );
document.write( "divide both sides of the equation by -1 to get x = 8<BR>\n" );
document.write( "since x + y = 15 and x = 8, then 8 + y = 15.<BR>\n" );
document.write( "solve for y to get y = 7.<BR>\n" );
document.write( "you now have x = 8 and y = 7<BR>\n" );
document.write( "substitute 8 for x and 7 for y in both equations to confirm that these solutions are good.<BR>\n" );
document.write( "x + y = 15 becomes 8 + 7 = 15 which becomes 15 = 15 which is true.<BR>\n" );
document.write( "2x + 3y = 37 becomes 2*8 + 3*7 = 37 which becomes 16 + 21 = 37 which becomes 37 = 37 which is true.<BR>\n" );
document.write( "the solutions for x and y are good.<BR>\n" );
document.write( "x = 8<BR>\n" );
document.write( "y = 7<BR>\n" );
document.write( "question is how many tricycles are there?<BR>\n" );
document.write( "answer is 7 because y represents the number of tricycles.<BR>\n" );
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