document.write( "Question 745110: The height s, in feet, of a rock thrown upward at an initial speed of 64 ft/sec from a cliff 50 ft above an ocean beach is given by the function s(t)=-16t^2+64t+50, where t is the time in seconds. Find the maximum height above the beach that the rock will attain. \n" ); document.write( "
Algebra.Com's Answer #453737 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
The maximum height of this parabolic curve is
\n" ); document.write( "\"+s%5Bmax%5D+\" when \"+t+=+-b%2F%282a%29+\" and
\n" ); document.write( "the equation has the form:
\n" ); document.write( "\"+s%28t%29+=+at%5E2+%2B+b%2At+%2B+c+\"
\n" ); document.write( "In your equation,
\n" ); document.write( "\"+s%28t%29+=+-16t%5E2+%2B+64t+%2B+50+\"
\n" ); document.write( "\"+a+=+-16+\"
\n" ); document.write( "\"+b+=+64+\", so
\n" ); document.write( "\"+t+=+-64+%2F+%28+2%2A%28-16%29%29+\"
\n" ); document.write( "\"+t+=+-64+%2F+-32+\"
\n" ); document.write( "\"+t+=+2+\" sec
\n" ); document.write( "--------------
\n" ); document.write( "Now find \"+s%282%29+\" which is the maximum height
\n" ); document.write( "\"+s%282%29+=+-16%2A2%5E2+%2B+64%2A2+%2B+50+\"
\n" ); document.write( "\"+s%282%29+=+-64+%2B+128+%2B+50+\"
\n" ); document.write( "\"+s%282%29+=+114+\" ft
\n" ); document.write( "The maximum height is 114 ft
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-2%2C+5%2C+-10%2C+130%2C+-16x%5E2+%2B+64x+%2B+50+%29+\"\r
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