document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1092505>Question 1092505</A>: <I><SPAN STYLE=\"word-break: break-all;\"> an object in launched upward at 110 feet per second from a platform 75 feet high . \r<BR>\n" );
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document.write( "a) When will the object be 120 feet high?\r<BR>\n" );
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document.write( "b) What is its maximum height?\r<BR>\n" );
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document.write( "c) When will it reach the ground?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #707125 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=707125\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the equation is -16t^2+110t+75, which accounts for the launch velocity and height.<BR>\n" );
document.write( "-16t^2+110t+75=120<BR>\n" );
document.write( "-16t^2+110t-45=0;  16t^2-110t+45<BR>\n" );
document.write( "t=(1/32)(110+/- sqrt (12100-2880); sqrt 9220=96.02, use 96<BR>\n" );
document.write( "t=0..4375 sec and 6.4375 sec.  Note, one uses both roots here.<BR>\n" );
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document.write( "maximum height is at time t=-b/2a=110/32 or 3.44 sec. If I use exact answer or 3.4375 the height is 264.0625 feet, 264 feet. If I use 3.44 sec the height is 264 feet.<BR>\n" );
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document.write( "hits ground when 16x^2-110x-75=0<BR>\n" );
document.write( "x^2-110x-1200=0 divide first term by 16 and multiply last by 16<BR>\n" );
document.write( "(x-120)(x+10)=0<BR>\n" );
document.write( "divide constants by 16 and reduce to lowest terms<BR>\n" );
document.write( "(x-(15/2))(x+(5/8))=0<BR>\n" );
document.write( "move the denominator out front<BR>\n" );
document.write( "(2x-15)(8x+5)=0 <BR>\n" );
document.write( "Postitive root is x=7.5 seconds.<BR>\n" );
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