document.write( "Question 177924: A paper airplane follows a parabolic path with h=-1/4t^2+t+3, where h is the height in meters, and t is the time in seconds. Algebraically determine how long it takes for the paper airplane to hit the ground. \n" ); document.write( "

Algebra.Com's Answer #133003 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

You can put this solution on YOUR website!
A paper airplane follows a parabolic path with h=-1/4t^2+t+3, where h is the height in meters, and t is the time in seconds. Algebraically determine how long it takes for the paper airplane to hit the ground.
\n" ); document.write( ":
\n" ); document.write( "When the plane hits the ground, h = 0. so we have:
\n" ); document.write( "-1/4t^2 + t + 3 = 0
\n" ); document.write( "multiply equation by -4 to get rid of the denominator & changes the sign.
\n" ); document.write( "t^2 - 4t - 12 = 0
\n" ); document.write( "factor
\n" ); document.write( "(t - 6)(t + 2) = 0
\n" ); document.write( "Positive solution
\n" ); document.write( "t = 6 seconds
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution in original equation: t=6
\n" ); document.write( "h = -1/4(6^2) + 6 + 3
\n" ); document.write( "h = -1/4(36) + 6 + 3
\n" ); document.write( "h = -9 + 9
\n" ); document.write( "h = 0
\n" ); document.write( " \n" ); document.write( "

\n" );