document.write( "Question 926546: y=-16x^2+44x+30 represents the height of an object (in feet) that is fired up from an initial height and then lands on the ground some time (in seconds) later.
\n" ); document.write( "a) From what height was the object launched?
\n" ); document.write( "b) How high will the object reach? At what time will this occur?
\n" ); document.write( "c) For how many seconds will the object be in the air?
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Algebra.Com's Answer #562319 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
\"+y+=+-16x%5E2+%2B+44x+%2B+30+\"
\n" ); document.write( "If \"+y+\" is feet and \"+x+\" is seconds,
\n" ); document.write( "The object is fired up at \"+x+=+0+\", so
\n" ); document.write( "the initial height is:
\n" ); document.write( "\"+y%280%29+=+-16x%5E2+%2B+44%2A0+%2B+30+\"
\n" ); document.write( "\"+y%280%29+=+30+\"
\n" ); document.write( "(a) 30 ft
\n" ); document.write( "----------------
\n" ); document.write( "When the form of the equation is:
\n" ); document.write( "\"+y+=+a%2Ax%5E2+%2B+b%2Ax+%2B+c+\", the time of the
\n" ); document.write( "maximum height is:
\n" ); document.write( "\"+x%5Bmax%5D+=+-b%2F%282a%29+\"
\n" ); document.write( "\"+-b%2F%282a%29+=+-44%2F%28+2%2A%28-16%29%29+\"
\n" ); document.write( "\"+-b%2F%282a%29+=+11%2F8+\"
\n" ); document.write( "-------------------
\n" ); document.write( "To find \"+y%5Bmax%5D+\":
\n" ); document.write( "\"+y%5Bmax%5D+=+-16%2A%2811%2F8%29%5E2+%2B+44%2A%2811%2F8%29+%2B+30+\"
\n" ); document.write( "\"+y%5Bmax%5D+=+-16%2A%28+121%2F64+%29+%2B+121%2F2+%2B+30+\"
\n" ); document.write( "\"+y%5Bmax%5D+=+-30.25+%2B+60.5+%2B+30+\"
\n" ); document.write( "\"+y%5Bmax%5D+=+60.25+\"
\n" ); document.write( "(b) 60.25 ft
\n" ); document.write( "----------------
\n" ); document.write( "The object is in the air until it hits the ground when
\n" ); document.write( "\"+y+=+0+\"
\n" ); document.write( "\"+0+=+-16x%5E2+%2B+44x+%2B+30+\"
\n" ); document.write( "\"+-8x%5E2+%2B+22x+%2B+15+=+0+\"
\n" ); document.write( "-------------------------
\n" ); document.write( "use quadratic formula:
\n" ); document.write( "\"+x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"
\n" ); document.write( "\"+x+=+%28-22+%2B-+sqrt%28+22%5E2+-+4%2A%28-8%29%2A15+%29%29+%2F+%282%2A%28-8%29%29+\"
\n" ); document.write( "\"+x+=+%28-22+%2B-+sqrt%28+484+%2B+480%29%29+%2F+%28-16%29+\"
\n" ); document.write( "\"+x+=+%28+-22+%2B+sqrt%28+964+%29+%29+%2F+%28-16%29+\"
\n" ); document.write( "\"+x+=+%28+-22+-+31.048+%29+%2F+%28-16%29+\"
\n" ); document.write( "\"+x+=+-53.048+%2F+%28-16%29+\"
\n" ); document.write( "\"+x+=+3.3155+\"
\n" ); document.write( "(c) 3.3155 sec
\n" ); document.write( "-----------------
\n" ); document.write( "check:
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-1%2C+5%2C+-10%2C+70%2C+-16x%5E2+%2B+44x+%2B+30+%29+\"\r
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