document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=471804>Question 471804</A>: <I><SPAN STYLE=\"word-break: break-all;\">  A projectile is fired from a cliff 100 feet above the water at an inclination of 45° to the horizontal, with a muzzle velocity of 170 feet per second. The height h of the projectile above the water is given by <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++h%28x%29=%28-32x%5E2%29%2F%28%28170%29%5E2%29%2Bx%2B100+ ALIGN=MIDDLE  ALT=\"++h%28x%29=%28-32x%5E2%29%2F%28%28170%29%5E2%29%2Bx%2B100+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where x is the horizontal distance of the projectile from the base of the cliff. How far from the base of the cliff is the height of the projectile a maximum? \r<BR>\n" );
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document.write( "A. 225.78 ft <BR>\n" );
document.write( "B. 451.56 ft <BR>\n" );
document.write( "C. 325.78 ft <BR>\n" );
document.write( "D. 777.34 ft \r<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 #323636 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=323636\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A projectile is fired from a cliff 100 feet above the water at an inclination of 45° to the horizontal, with a muzzle velocity of 170 feet per second. The height h of the projectile above the water is given by<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++h%28x%29=%28-32x%5E2%29%2F%28%28170%29%5E2%29%2Bx%2B100+ ALIGN=MIDDLE  ALT=\"++h%28x%29=%28-32x%5E2%29%2F%28%28170%29%5E2%29%2Bx%2B100+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where x is the horizontal distance of the projectile from the base of the cliff. How far from the base of the cliff is the height of the projectile a maximum?<BR>\n" );
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document.write( "Convert the coefficient of x^2 to a more manageable value<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-32%2F10%5E2 ALIGN=MIDDLE  ALT=\"-32%2F10%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -.001107, so we have<BR>\n" );
document.write( "h(x) = -.001107x^2 + x + 100<BR>\n" );
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document.write( "find the axis of symmetry, x = -b/(2a), in this equation a=-.001107, b=1<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-1%29%2F%282%2A-.001107%29 ALIGN=MIDDLE  ALT=\"%28-1%29%2F%282%2A-.001107%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = +451.6 ft from the base of the cliff, it will be at max height\r<BR>\n" );
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