document.write( "Question 908390: A fireworks shell is shot straight up with an initial velocity of 80 feet per second. Its height s after t seconds is given by the equation
\n" ); document.write( "s = 80t − 16t2.
\n" ); document.write( " If the shell is designed to explode when it reaches its maximum height, how long after being fired, and at what height, will the fireworks appear in the sky?\r
\n" ); document.write( "\n" ); document.write( "time=_______ sec
\n" ); document.write( "height=_________ft \n" ); document.write( "
Algebra.Com's Answer #551004 by lwsshak3(11628)\"\" \"About 
You can put this solution on YOUR website!
A fireworks shell is shot straight up with an initial velocity of 80 feet per second. Its height s after t seconds is given by the equation
\n" ); document.write( "s = 80t − 16t2.
\n" ); document.write( "If the shell is designed to explode when it reaches its maximum height, how long after being fired, and at what height, will the fireworks appear in the sky?
\n" ); document.write( "***
\n" ); document.write( "s=80t-16t^2
\n" ); document.write( "s=-16t^2+80t
\n" ); document.write( "complete the square
\n" ); document.write( "s=-16(t^2-5t+25/4)+100
\n" ); document.write( "s=-16(t-2.5)^2+100
\n" ); document.write( "how long after being fired, and at what height, will the fireworks appear in the sky? 2.5 sec at a height of 100 ft \n" ); document.write( "
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