document.write( "Question 1066433: A projectile is launched upward with a velocity of 160 feet per second from the top of a 70-foot platform. What is the maximum height attained by the projectile? \n" ); document.write( "

Algebra.Com's Answer #681581 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
The equation would be:
\n" ); document.write( " $\"+h%28t%29+=+-16t%5E2+%2B+160t+%2B+70+\"$
\n" ); document.write( "This is a parabola with a peak ( not a dip )
\n" ); document.write( "The formula for the x-value of the peak is
\n" ); document.write( " $\"+x%5Bp%5D+=+-b%2F%282a%29+\"$
\n" ); document.write( " $\"+x%5Bp%5D+=+-160%2F%28+2%2A%28-16%29+%29+\"$
\n" ); document.write( " $\"+x%5Bp%5D+=+160%2F32+\"$
\n" ); document.write( " $\"+x%5Bp%5D+=+5+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "Plug this value back into equation to get $\"+h%5Bp%5D+\"$
\n" ); document.write( " $\"+h%5Bp%5D+=+-16%2A5%5E2+%2B+160%2A5+%2B+70+\"$
\n" ); document.write( " $\"+h%5Bp%5D+=+-16%2A25+%2B+800+%2B+70+\"$
\n" ); document.write( " $\"+h%5Bp%5D+=+-400+%2B+800+%2B+70+\"$
\n" ); document.write( " $\"+h%5Bp%5D+=+470+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "The maximum height is 470 ft
\n" ); document.write( "---------------------
\n" ); document.write( "check:
\n" ); document.write( "Here's the plot:
\n" ); document.write( " $\"+graph%28+500%2C+500%2C+-2%2C+12%2C+-60%2C+600%2C+-16x%5E2+%2B+160x+%2B+70+%29+\"$ \r
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