document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1074231>Question 1074231</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The Krakow airport is 3 km west and 5 km north of the city center. At 1 pm, Zuza<BR>\n" );
document.write( "took off in a Cessna 730. Every six minutes, the plane’s position changed by 9 km east and<BR>\n" );
document.write( "7 km north. At 2:30 pm, Zuza was flying over the town of Jozefow. In relation to the center<BR>\n" );
document.write( "of Krakow, (a) where is Jozefow? (b) where was Zuza after t hours of flying? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #689016 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=689016\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x = the number of km east of krakow center.<BR>\n" );
document.write( "let y = the number of km north of krakow center.\r<BR>\n" );
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document.write( "when t = 0, the position of the plane is 3km west and 5 km north of krakow center.\r<BR>\n" );
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document.write( "3 km west is the same as -3 km east.\r<BR>\n" );
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document.write( "if we graph the location of the plane, using x = number of km east of krakow center and y = number of km north of krakow center, then, if we assume krakow center is at point (0,0), the plane starts off at the point (-3,5).\r<BR>\n" );
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document.write( "x = -3 means the plane is -3 km east which is the same as 3 km west.<BR>\n" );
document.write( "y = 5 means the plane is 5 km north.\r<BR>\n" );
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document.write( "if we let t = hours, then every 6 minute increment will be .1 * t.\r<BR>\n" );
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document.write( "for every 6 minute increment, the plane travels 1 * 9 km east and 1 * 7 km north.\r<BR>\n" );
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document.write( "therefore, for every 60 minute increment, the plane travels 10 * 9 km east and 10 * 7 km north.\r<BR>\n" );
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document.write( "simplify this to get:\r<BR>\n" );
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document.write( "the plane travels 90km east and 70 km north every 60 minutes.\r<BR>\n" );
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document.write( "since 60 minutes is equal to 1 hour, then you get:\r<BR>\n" );
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document.write( "the plane travels 90 km east and 70 km north every hour.\r<BR>\n" );
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document.write( "your equation for y and x in terms of t becomes:\r<BR>\n" );
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document.write( "x = 90 * t + b and y = 70 * t + b.\r<BR>\n" );
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document.write( "b represents the value of x or y when t = 0.\r<BR>\n" );
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document.write( "since the plane starts at x = -3 and y = 4, then your equation for x and y in terms of t becomes:\r<BR>\n" );
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document.write( "x = 90 * t - 3 and y = 70 * t + 5\r<BR>\n" );
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document.write( "when t = 0, you get x = -3 and y = 5<BR>\n" );
document.write( "when t = 1, you get x = 87 and y = 75<BR>\n" );
document.write( "when t = 2, you get x = 177 and y = 145\r<BR>\n" );
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document.write( "after t hours, the plane is 90 * t - 3 km east of krakow center and 70 * t + 5 km north of krakow center.\r<BR>\n" );
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document.write( "since the plane starts at 1:00 pm and is over jozefow at 2:30 pm, then t = 1.5 and the plane is 90 * 1.5 - 3 km east of krakow center and 70 * 1.5 + 5 km north of krakow center.\r<BR>\n" );
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document.write( "that puts the plane at 132 km east of krakow center and 110 km north of krakow center.\r<BR>\n" );
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document.write( "that means jozefow is 132 km east of krakow center and 110 km north of krakow center.\r<BR>\n" );
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document.write( "i could be wrong, but i believe that i did it right and that the above answers are the solutions you are looking for.\r<BR>\n" );
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document.write( "your solutions should be:\r<BR>\n" );
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document.write( "x = 90 * t - 3<BR>\n" );
document.write( "y = 70 * t + 5<BR>\n" );
document.write( "jozefow is 132 km east and 110 km north of krakow center.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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