document.write( "Question 195718: A baseball player has hit a ball. The height, y, of the ball x seconds after it is hit is given by y= -16x^2 + 80x + 3.
\n" );
document.write( "At what time will the ball reach its maximum height? I used the quadratic formula and my answer was 2.04
\n" );
document.write( "What is the maximum height of the ball? I used the original formula.My answer was 232.78
\n" );
document.write( "When will the ball hit the ground? My answer was 4.08\r
\n" );
document.write( "\n" );
document.write( "Is this right??
\n" );
document.write( "thanks \n" );
document.write( "
Algebra.Com's Answer #146754 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! At what time will the ball reach its maximum height? \n" ); document.write( "What is the maximum height of the ball?\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "First, we need the vertex. The vertex will tell us what the max height will be:\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "In order to find the vertex, we first need to find the x-coordinate of the vertex.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "To find the x-coordinate of the vertex, use this formula: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "From \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the x-coordinate of the vertex is \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now that we know the x-coordinate of the vertex, we can use it to find the y-coordinate of the vertex.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the y-coordinate of the vertex is \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the vertex is \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "which in decimal form is \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So this means that at 2.5 seconds, the ball will be at the max height of 103.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "When will the ball hit the ground?\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the possible answers are \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "which approximate to \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since a negative time doesn't make sense, this means that the only solution is \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So it will take about 5.037 seconds for the ball to hit the ground.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |