document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=470978>Question 470978</A>: <I><SPAN STYLE=\"word-break: break-all;\"> h(t)= c-(d-4t)^2; At time t=0, an initial height of 6 feet.  Until the ball hit the ground, its height in feet after t seconds was given by the function h (at the beginning of problem), in which c and d are positive constants.  If the ball reached its maximum height of 106 feet at time t=2.5, what was the height in feet of the ball at t=1 ?\r<BR>\n" );
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document.write( "The answer is 70, but I do not understand how they came up with this answer....please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #323041 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=323041\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> h(t)= c-(d-4t)^2; At time t=0, an initial height of 6 feet.  Until the ball hit the ground, its height in feet after t seconds was given by the function h (at the beginning of problem), in which c and d are positive constants.  If the ball reached its maximum height of 106 feet at time t=2.5, what was the height in feet of the ball at t=1 ?<BR>\n" );
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document.write( "Solve for c & d<BR>\n" );
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document.write( "h(t)= c-(d-4t)^2<BR>\n" );
document.write( "h(0) = c - d^2 = 6<BR>\n" );
document.write( "h(2.5) = c - (d - 10)^2 = 106<BR>\n" );
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document.write( "c - d^2 = 6<BR>\n" );
document.write( "c = d^2 + 6<BR>\n" );
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document.write( "c - (d - 10)^2 = 106<BR>\n" );
document.write( "c - d^2 + 20d - 100 = 106<BR>\n" );
document.write( "Sub for c<BR>\n" );
document.write( "d^2+6 - d^2 + 20d = 206<BR>\n" );
document.write( "20d = 200<BR>\n" );
document.write( "d = 10<BR>\n" );
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document.write( "c = 106<BR>\n" );
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document.write( "h(t) = 106 - (10 - 4t)^2<BR>\n" );
document.write( "h(1) = 106 - 6^2<BR>\n" );
document.write( "h(1) = 70<BR>\n" );
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