document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=55204>Question 55204</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have this problem that I would like someone to check my work:\r<BR>\n" );
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document.write( "If a skydiver jumps from an airplane at a height of 8256 feet, then for the first five seconds, her height above the earth is approximated by the formula h = -16t^2 + 8256.  How many seconds does it take her to reach 8000 feet?\r<BR>\n" );
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document.write( "WORK DONE :\r<BR>\n" );
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document.write( "What I have done is:\r<BR>\n" );
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document.write( "h = 16^t + 8256<BR>\n" );
document.write( "h = -16t^2 + 8256 = 8000<BR>\n" );
document.write( "h = -16t^2 + 8256 - 8000 = 0<BR>\n" );
document.write( "-16t^2 + 256 = 0<BR>\n" );
document.write( "-16t^2 + 256 - 256 = - 256<BR>\n" );
document.write( "16t^2 = -256\r<BR>\n" );
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document.write( "-16t^2/16 = -256/-16\r<BR>\n" );
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document.write( "t^2 = 16\r<BR>\n" );
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document.write( "t = 4\r<BR>\n" );
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document.write( "I'm  not confident about the way I have worked this out.  Could someone check.<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 #37459 by </B><A HREF=/tutors/aboutme.mpl?userid=venugopalramana><B>venugopalramana(3286)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=venugopalramana><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.geocities.com/venugopalramana/FREE_MATHS_ASSISTANCE.html valign=middle><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=37459\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> SEE MY COMMENTS BELOW...<BR>\n" );
document.write( "I have this problem that I would like someone to check my work: <BR>\n" );
document.write( "If a skydiver jumps from an airplane at a height of 8256 feet, then for the first five seconds, her height above the earth is approximated by the formula h = -16t^2 + 8256. How many seconds does it take her to reach 8000 feet? <BR>\n" );
document.write( "WORK DONE : <BR>\n" );
document.write( "What I have done is: <BR>\n" );
document.write( "h = 16^t + 8256....HOW?TYPING ERROR..IT SHOULD BE -16T^2+8256<BR>\n" );
document.write( "h = -16t^2 + 8256 = 8000...OK<BR>\n" );
document.write( "h = -16t^2 + 8256 - 8000 = 0...DONT WRITE H=...IT IS NOT CORRECT.<BR>\n" );
document.write( "SIMPLY WRITE<BR>\n" );
document.write( "-16T^2+8256-8000=0.....GOT IT?<BR>\n" );
document.write( "-16t^2 + 256 = 0...OK<BR>\n" );
document.write( "-16t^2 + 256 - 256 = - 256...OK<BR>\n" );
document.write( "16t^2 = -256 ......NO AGAIN TYPING ERROR? IT IS -16T^2=-256<BR>\n" );
document.write( "-16t^2/16 = -256/-16 .....OK<BR>\n" );
document.write( "t^2 = 16 ......OK<BR>\n" );
document.write( "t = 4 .....OK....<BR>\n" );
document.write( "I'm not confident about the way I have worked this out. Could someone check.<BR>\n" );
document.write( "THE ANSWER IS OK.THE WORKING IS FAULTY AT SOME PLACES AS MENTIONED.<BR>\n" );
document.write( "CORRECT THOSE ERRORS AND YOU WILL DO WELL.SEE THE FOLLOWING EXAMPLE ON SOLUTION OF EQNS.FOR PROPER STEPS OF WORKING.<BR>\n" );
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document.write( "I really don't understand this problem. Can you please help me?<BR>\n" );
document.write( "3(1-3x)+2=4x+14........OK<BR>\n" );
document.write( "3-9x+2=4x+14................GOOD<BR>\n" );
document.write( "so then add or subtract from both sides?<BR>\n" );
document.write( "3-9x+9x+2=13+14......HERE YOU GOT CONFUSED..<BR>\n" );
document.write( "THE STEPS INVOLVED ARE<BR>\n" );
document.write( "1.REMOVE BRACKETS ......THIS YOU HAVE DONE.<BR>\n" );
document.write( "2.TRANSFER ALL UNKNOWN TERMS TO ONE SIDE.... USUALLY L.H.S. AND KNOWN TERMS TO ONE SIDE ...USUALLY R.H.S.<BR>\n" );
document.write( "3.THIS TRANSFER YOU CAN THINK OF AND DO AS FOLLOWS....<BR>\n" );
document.write( "EVERY TERM HAS A + OR - SIGN INFRONT OF IT.WHEN YOU TRANSFER THAT TERM FROM ONE SIDE TO ANOTHER ,+ BECOMES - AND - BECOMES PLUS.<BR>\n" );
document.write( "THIS IS BECAUSE...AS YOU WERE TRYING TO SAY 'ADD OR SUBTRACT FROM BOTH SIDES'<BR>\n" );
document.write( "AN EQUATION IS UNALTERED IF WE ADD OR SUBTRACT SAME QUANTITY FROM BOTH SIDES OF THE EQN.SO IF WE WANT TO REMOVE +4X ABOVE FROM R.H.S.WE HAVE TO ADD -4X TO IT.SO TO BALANCE IT AND KEEP THE VALIDITY OF THE EQN.UNALTERED,WE ADD -4X TO L.H.S.ALSO.THEN ON R.H.S ,WE GET +4X-4X=0...THAT IS +4X DIAPPEARS AS WE WANTED.BUT -4X REMAINS ON L.H.S.....THIS IS THE FINAL EFFECT OF ADD AND SUBTRACT WHICH IS SUMMARISED FIRST ABOVE.<BR>\n" );
document.write( "HENCE WE GET HERE<BR>\n" );
document.write( "-9X-4X = 14-2-3 <BR>\n" );
document.write( "4.NOW SIMPLIFY BOTH SIDES COMBINING ALL UNKNOWNS ON L.H.S AND ALL KNOWNS ON R.H.S<BR>\n" );
document.write( "WE GET HERE <BR>\n" );
document.write( "-13X=9<BR>\n" );
document.write( "5.NOW TRANSFER THE COEFFICIENT OF UNKNOWN ON L.H.S.TO R.H.S.<BR>\n" );
document.write( "APPLYING THE SAME RULE & LOGIC MENTIONED ABOVE,HERE * WILL BECOME / AND / BECOMES *<BR>\n" );
document.write( "HERE WE GET<BR>\n" );
document.write( "X = -9/13....<BR>\n" );
document.write( "THIS IS THE ANSWER.<BR>\n" );
document.write( "6.IF YOU HAVE TIME AND WOULD LIKE TO DO....CHECK BACK THE ANSWER FOR CONFIRMATION BY SUBSTITUTION..<BR>\n" );
document.write( "3{1-3*(-9/13)}+2=4*(-9/13)+ 14<BR>\n" );
document.write( "3{1+27/13)+2=-36/13 +14<BR>\n" );
document.write( "3*40/13 +2=(-36+14*13)/13<BR>\n" );
document.write( "120/13 +2= 146/13<BR>\n" );
document.write( "146/13 = 146/13.......OK \r<BR>\n" );
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document.write( "You may edit the question. Maybe convert formulae  </SPAN>\n" );
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