document.write( "Question 1183267: Hi can you please help me with this question. A golf ball is hit from the top of a tee. The quadratic equation y=-5x^2 + 20x + 0.05 describes its height,y, in metres as time,x, in seconds passes. Determine how long the ball is in the air. Thanks for the help \n" ); document.write( "

Algebra.Com's Answer #813494 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "Hi can you please help me with this question. A golf ball is hit from the top of a tee. The quadratic equation y=-5x^2 + 20x + 0.05 describes its height,y, in metres as time,x, in seconds passes. Determine how long the ball is in the air. Thanks for the help
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Since time is x, the ball will be on the ground when y, or height = 0
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document.write( "Therefore, all you need to do is solve the quadratic. 
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document.write( "Using the quadratic equation formula, we get 2 solutions, as expected. They are: - .0025 and 4.0025 seconds.
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document.write( "Obviously, time, in this case, CANNOT be < 0 (negative), so time the ball was in the air is the LATTER. \n" );
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