document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=128099>Question 128099</A>: <I><SPAN STYLE=\"word-break: break-all;\"> tyrels and dalia bought some pens and pencils. tyrel bought 4 pensand 5 pencils, which cost him $6.71. dalia bought 5 pens and 3 pencils, which cost her $7.12. Let A equal the price of a pen. let B equal the price of a pencil. <BR>\n" );
document.write( "a. write an equation that relates the number of pens and pencils tyrel bought to the amount he paid for them.<BR>\n" );
document.write( "b. write an equation that relates the number of pens and pencils dalia bought to the amount she paid for them.<BR>\n" );
document.write( "c. solve the system you wrote for parts (a) and (b) to find the price of a pen and the price of a pencil.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #93804 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=93804\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> tyrel bought 4 pensand 5 pencils, which cost him $6.71. dalia bought 5 pens and 3 pencils, which cost her $7.12. Let A equal the price of a pen. let B equal the price of a pencil. <BR>\n" );
document.write( "a. write an equation that relates the number of pens and pencils tyrel bought to the amount he paid for them.<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "4A + 5B = 6.71<BR>\n" );
document.write( "5A + 3B = 7.12<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Multiply the 1st equation by 5 and the 2nd equation by 4 to get:<BR>\n" );
document.write( "20A + 25B = 5*6.71<BR>\n" );
document.write( "20A + 12B = 4*7.12<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "Subtract the 2nd equation from the 1st to get:<BR>\n" );
document.write( "13B = 5.07<BR>\n" );
document.write( "B = 39 cents (price of a pencil)<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Substitute to solve for A:<BR>\n" );
document.write( "4A + 5(0.39) = 6.71<BR>\n" );
document.write( "4A = 4.76<BR>\n" );
document.write( "A = $1.19 (price of a pen) <BR>\n" );
document.write( "-------------------------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );