document.write( "Question 91225: An object is dropped from an airplane flying 784 feet above the ground. The height 'h' above the ground 't' seconds after it is dropped is given by the formula h=16t+784. How long will it take for the object to hit the ground? \n" ); document.write( "

Algebra.Com's Answer #66214 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
When the object hits the ground, the height, h, will be zero. So if you set the formula for h equal to zero and solve for the time, t, this will tell you how long it will take for the object to hit the ground.\r
\n" ); document.write( "\n" ); document.write( "h = 16t + 784 ...but I think you may have a typo here! It should be:
\n" ); document.write( " $\"h+=+-16t%5E2+%2B+784\"$ So, set this = 0 and solve for t.
\n" ); document.write( " $\"0+=+-16t%5E2%2B784\"$ Add $\"16t%5E2\"$ to both sides.
\n" ); document.write( " $\"16t%5E2+=+784\"$ Divide both sides by 16.
\n" ); document.write( " $\"t%5E2+=+49\"$ Take the square root of both sides.
\n" ); document.write( " $\"t+=+7\"$ or $\"t+=+-7\"$ Discard the negative solution as the time, t, should be a positive value.
\n" ); document.write( "It will take the object 7 seconds to hit the ground. \n" ); document.write( "

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