document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=708281>Question 708281</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A projectile is launched from the ground with an initial velocity of V0 feet per second. Neglecting air resistance, its height in feet per seconds after launch is given by s = -16t^2 +V0t. Find the time(s) that the projectile will\r<BR>\n" );
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document.write( "(a) reach a height of 240ft and <BR>\n" );
document.write( "(b) return to the ground when V0= 128 feet per second. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #436042 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=436042\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "(a)  Set the function equal to 240.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE -16t^2\ +\ v_ot\ =\ 240\">\r<BR>\n" );
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document.write( "Substitute your given value of <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE v_o\"> and then solve the quadratic.  The equation will have two zeros, one representing the time the projectile reaches 240 feet on the way up, and the other representing the time the projectile passes 240 feet again on the way back down.\r<BR>\n" );
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document.write( "(b)  Same as part (a) except you set the function equal to the height of the ground, i.e. zero.  Your two zeros will be zero and some positive number.  The zero root represents the instant of launch, and the other is the time of return to ground.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "<font face=\"Math1\" size=\"+2\">Egw to Beta kai to Sigma</font><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it<BR>\n" );
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