document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171929>Question 171929</A>: <I><SPAN STYLE=\"word-break: break-all;\"> suppose that an object is thrown into the air with an intial upward velocity of vo meters per second from a height ho meters above the ground. Then t seconds later, its height h(t) meters above the ground is modeled by the function h(t)= -4.9 t^2 + vot + ho. (this model dosent' account for resistance)\r<BR>\n" );
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document.write( "if a stone is thrown with an upward velocity of 14 m/s from a cliff 30 meters high \r<BR>\n" );
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document.write( "I answered part a which asked:\r<BR>\n" );
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document.write( "a. find its height above the ground t seconds later.\r<BR>\n" );
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document.write( "h(t)= -4.9t^2 + 14 t + 30\r<BR>\n" );
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document.write( "I don't understand part b or c\r<BR>\n" );
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document.write( "b. when will the stone reach it's highest elevation<BR>\n" );
document.write( "c.when will the stone hit the ground?\r<BR>\n" );
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document.write( "I would really appreciate any help I can recieve. <BR>\n" );
document.write( "Thank you very much<BR>\n" );
document.write( "please help soon! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #127186 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=127186\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> suppose that an object is thrown into the air with an intial upward velocity of vo meters per second from a height ho meters above the ground. Then t seconds later, its height h(t) meters above the ground is modeled by the function h(t)= -4.9 t^2 + vot + ho. (this model dosent' account for resistance)\r<BR>\n" );
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document.write( "if a stone is thrown with an upward velocity of 14 m/s from a cliff 30 meters high<BR>\n" );
document.write( "I answered part a which asked:<BR>\n" );
document.write( "a. find its height above the ground t seconds later.<BR>\n" );
document.write( "h(t)= -4.9t^2 + 14t + 30<BR>\n" );
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document.write( "I don't understand part b or c<BR>\n" );
document.write( "b. when will the stone reach it's highest elevation<BR>\n" );
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document.write( "It will reach the highest point (max) on the axis of symmetry<BR>\n" );
document.write( "Find the axis of symmetry using the formula: x = -b/(2a)<BR>\n" );
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document.write( "In this problem x=t, a=-4.9, b=14, we have:<BR>\n" );
document.write( "t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-14%29%2F%282%2A-4.9%29 ALIGN=MIDDLE  ALT=\"%28-14%29%2F%282%2A-4.9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-14%29%2F%28-9.8%29 ALIGN=MIDDLE  ALT=\"%28-14%29%2F%28-9.8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = +1.43 seconds, it will be at it's highest point<BR>\n" );
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document.write( "c.when will the stone hit the ground? <BR>\n" );
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document.write( "When it hits the ground h(t) = 0, find t: we have;<BR>\n" );
document.write( "-4.9t^2 + 14t + 30 = 0<BR>\n" );
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document.write( "Solve for t using the quadratic formula: a=-4.9, b=14, c=30<BR>\n" );
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document.write( "You should get a positive solution of about 4.28 seconds<BR>\n" );
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document.write( "A graph of this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+200%2C+-1%2C+5%2C+-10%2C+50%2C+-4.9x%5E2%2B14x%2B30%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+200%2C+-1%2C+5%2C+-10%2C+50%2C+-4.9x%5E2%2B14x%2B30%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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