document.write( "Question 906061: A ball is thrown across a playing field. Its path is given by the equation y = −0.005 x^2 + x + 6 , where x is the distance the ball has traveled horizontally, and y is its height above ground level, both measured in feet.\r
\n" ); document.write( "\n" ); document.write( "(a) What is the maximum height attained by the ball?
\n" ); document.write( "
\n" ); document.write( "(b) How far has it traveled horizontally when it hits the ground?
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #549622 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
\"+y+=+-.005%2A+x%5E2+%2B+x+%2B+6+\"
\n" ); document.write( "Find \"+y%5Bmax%5D+\"
\n" ); document.write( "The x-coordinate of the vertex is located at
\n" ); document.write( "\"+x%5Bmax%5D+=+-b%2F%282a%29+\"
\n" ); document.write( "\"+x%5Bmax%5D+=+-1+%2F+%28+2%2A%28-.005%29+%29+\"
\n" ); document.write( "\"+x%5Bmax%5D+=+1%2F.01+\"
\n" ); document.write( "\"+x%5Bmax%5D+=+100+\"
\n" ); document.write( "and
\n" ); document.write( "\"+y%5Bmax%5D+=+-.005%2A+100%5E2+%2B+100+%2B+6+\"
\n" ); document.write( "\"+y%5Bmax%5D+=+-50+%2B+106+\"
\n" ); document.write( "\"+y%5Bmax%5D+=+56+\"
\n" ); document.write( "(a)
\n" ); document.write( "The max height is 56 ft
\n" ); document.write( "(b)
\n" ); document.write( "It hits the ground when \"+y+=+0+\"
\n" ); document.write( "\"+-.005%2A+x%5E2+%2B+x+%2B+6+=+0+\"
\n" ); document.write( "Multiply both sides by \"+-200+\"
\n" ); document.write( "\"+x%5E2+-+200x+-+1200+=+0+\"
\n" ); document.write( "\"+x%5E2+-+200x+=+1200+\"
\n" ); document.write( "\"+x%5E2+-+200x+%2B+%28+200%2F2+%29%5E2+=+1200+%2B+%28+200%2F2+%29%5E2+\"
\n" ); document.write( "\"+x%5E2+-+200x+%2B+10000+=+11200+\"
\n" ); document.write( "\"+%28+x+-+100+%29%5E2+=+11200+\"
\n" ); document.write( "\"+x++-+100+=+105.83+\"
\n" ); document.write( "\"+x+=+205.83+\"
\n" ); document.write( "When it hits the ground, it has traveled 205.83 ft
\n" ); document.write( "-----------------
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+220%2C+-5%2C+60%2C+-.005%2Ax%5E2+%2B+x+%2B+6+%29+\" \r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );