document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1099680>Question 1099680</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A projectile is fired from a cliff 1488 feet above the water at inclination of 45 degrees to the horizontal, with a velocity of 720 feet per second. The h of the projectile can be modeled by:\r<BR>\n" );
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document.write( "h(x)=-32x^2/720^2+x+1488<BR>\n" );
document.write( "Where x is the horizontal distance of the projectile from the firing point\r<BR>\n" );
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document.write( "At what horizontal distance from the firing point will the projectile hit the ground? Feet:\r<BR>\n" );
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document.write( "I got the other parts to the question correct and finished. I cannot seem to get this last part to the problem correct. I have tried setting h(x) to zero but the answer never seems to come out right. Any help with would very appreciated, Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #714117 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=714117\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> set y = h(x) and you get:\r<BR>\n" );
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document.write( "y = -32x^2 / 720^2 + x + 1488\r<BR>\n" );
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document.write( "when you set y equal to 0, the formula becomes:\r<BR>\n" );
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document.write( "-32x^2 / 720^2 + x + 1488 = 0\r<BR>\n" );
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document.write( "this is a quadratic equation in standard form of ax^2 + bx + x = 0\r<BR>\n" );
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document.write( "therefore a = -32/720^2 and b = 1 and c =1488.\r<BR>\n" );
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document.write( "use the quadratic formula to solve this equation.\r<BR>\n" );
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document.write( "the formula states that:\r<BR>\n" );
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document.write( "x = (-b - sqrt(b^2 - 4ac)) / (2a) \r<BR>\n" );
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document.write( "or:\r<BR>\n" );
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document.write( "x = (-b + sqrt(b^2 - 4ac)) / (2a) \r<BR>\n" );
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document.write( "from there, it's a simple matter of replacing a,b,c with their respective values.\r<BR>\n" );
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document.write( "you will get:\r<BR>\n" );
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document.write( "x = (-1 - sqrt(1^2 - 4 * -32/720^2 * 1488)) / (2 * -32/720^2) \r<BR>\n" );
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document.write( "or:\r<BR>\n" );
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document.write( "x = (-1 + sqrt(1^2 - 4 * -32/720^2 * 1488)) / (2 * -32/720^2) \r<BR>\n" );
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document.write( "this becomes:\r<BR>\n" );
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document.write( "x = 17571.83192\r<BR>\n" );
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document.write( "or:\r<BR>\n" );
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document.write( "x = -1371.831924\r<BR>\n" );
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document.write( "if you have good graphing software, like the one found at <a  rel=nofollow HREF= \"https://www.desmos.com/calculator\" target = \"_blank\">https://www.desmos.com/calculator</a>, then you can graph the equation of y = -32x^2 / 720^2 + x + 1488 and you will get what is shown below after adjusting the x and y limits correctly.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2017/103101.jpg\" alt=\"$$$\" > </SPAN>\n" );
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