document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1056748>Question 1056748</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Airplane A travels 2800<BR>\n" );
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document.write( "km at a certain speed. Plane B travels 2000<BR>\n" );
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document.write( "km at a speed 50 km divided by h<BR>\n" );
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document.write( "faster than plane A in 3 hrs less time. Find the speed of each plane. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #671829 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=671829\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Airplane A travels 2800 km at a certain speed<BR>\n" );
document.write( " Plane B travels 2000 km at a speed 50 km/hr faster than plane A in 3 hrs less time.<BR>\n" );
document.write( " Find the speed of each plane.<BR>\n" );
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document.write( "let s = the speed of Plane A<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+50) = the speed of B<BR>\n" );
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document.write( "Write a time equation, time = dist/speed<BR>\n" );
document.write( "A time - b Time = 3 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2800%2Fs ALIGN=MIDDLE  ALT=\"2800%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2000%2F%28%28s%2B50%29%29 ALIGN=MIDDLE  ALT=\"2000%2F%28%28s%2B50%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 3<BR>\n" );
document.write( "multiply equation by s(s+50), cancel the denominators<BR>\n" );
document.write( "2800(s+50) - 2000s = 3s(s+50)<BR>\n" );
document.write( "2800s + 140000 - 2000s = 3s^2 + 150s<BR>\n" );
document.write( "800s + 140000 = 3s^2 + 150s<BR>\n" );
document.write( "0 = 3s^2 + 150s - 800s - 140000<BR>\n" );
document.write( "A quadratic equation<BR>\n" );
document.write( "3s^2 - 650s - 140000 = 0<BR>\n" );
document.write( "You can use the quadratic formula, but this will factor to<BR>\n" );
document.write( "(3s+400)(s-350)<BR>\n" );
document.write( "the positive solution is what we want here<BR>\n" );
document.write( "s = 350 mph for plane A and obviously, 400 mph for place B<BR>\n" );
document.write( "and<BR>\n" );
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