document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=828174>Question 828174</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.) A rocket is 1 mile above the earth 30 seconds after lifting off. The rocket is 5 miles above the earth after 2.5 minutes. \r<BR>\n" );
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document.write( "a) Write an equation that represents this situation.\r<BR>\n" );
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document.write( "b) What does the slope represent in this situation? The y-intercept?\r<BR>\n" );
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document.write( "P.S. Could you also show me how you got the answers? Thanks! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #499104 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=499104\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> At liftoff the rocket is at ground level, 0 miles above earth's surface.<BR>\n" );
document.write( "After 30 seconds, it is 1 mile above earth's surface.<BR>\n" );
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document.write( "a) The average upwards speed of the rocket during the first 30 seconds (0.5 minutes) is<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1mile%2F%220.5+minutes%22=2 ALIGN=MIDDLE  ALT=\"1mile%2F%220.5+minutes%22=2\"   DISABLED_style= \"max-width:90%; height:auto;\" >miles per minute.<BR>\n" );
document.write( "The average upwards speed of the rocket during the next 2 minutes (between 30 seconds and 2.5 minutes after liftoff) in miles per minute is<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%285-1%29%2F%282.5-0.5%29=4%2F2=2 ALIGN=MIDDLE  ALT=\"%285-1%29%2F%282.5-0.5%29=4%2F2=2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "It may not be scientifically sound to assume that the speed was 2 miles per minute at all times, but my guess is that your teacher intended exactly that.<BR>\n" );
document.write( "So the height <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" > of the rocket (in miles), as a function of time <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" > (in minutes) since liftoff is<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%28t%29=2t ALIGN=MIDDLE  ALT=\"h%28t%29=2t\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "If you called the height in miles <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y ALIGN=MIDDLE  ALT=\"y\"   DISABLED_style= \"max-width:90%; height:auto;\" > and the time in minutes <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x ALIGN=MIDDLE  ALT=\"x\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "then the equation would be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=2x ALIGN=MIDDLE  ALT=\"y=2x\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "Either way, the function is a linear function.<BR>\n" );
document.write( "Its graph is a straight line through the origin.<BR>\n" );
document.write( "I would graph it only for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%3E=0 ALIGN=MIDDLE  ALT=\"t%3E=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > because we do not know where that rocket was before liftoff (for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%3C0 ALIGN=MIDDLE  ALT=\"t%3C0\"   DISABLED_style= \"max-width:90%; height:auto;\" > ).<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28300%2C300%2C-0.5%2C4.5%2C-2%2C8%2C%0D%0Agrid%281%29%2C%0D%0Aline%280%2C0%2C4%2C8%29+%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "b) The slope in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=2x%2B0 ALIGN=MIDDLE  ALT=\"y=2x%2B0\"   DISABLED_style= \"max-width:90%; height:auto;\" > is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2 ALIGN=MIDDLE  ALT=\"2\"   DISABLED_style= \"max-width:90%; height:auto;\" > miles per minute and represents the speed of the rocket.<BR>\n" );
document.write( "The y-intercept is 0 miles, because the graph crosses the y-axis at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=0 ALIGN=MIDDLE  ALT=\"y=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "The y-intercept represents the height of the rocket at liftoff: 0 miles above earth. </SPAN>\n" );
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