document.write( "Question 1111603: an object is projected straight up with an initial velocity of k ft. /sec. The height of the object, h, at any time, t, is given by the function h(t)= -16t^2+ kt. if the object returns to the ground at t=8 sec., find the height (in feet) of the object at t=7 sec.Explain in words your steps to finding the value of k.\r
\n" ); document.write( "\n" ); document.write( "I tried to find k but i could finish because i didn't know what to do after u plug in the numbers and simplify also i got a crazy number when i didn't simplify \n" ); document.write( "
Algebra.Com's Answer #726596 by ankor@dixie-net.com(22740)\"\" \"About 
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an object is projected straight up with an initial velocity of k ft. /sec.
\n" ); document.write( " The height of the object, h, at any time, t, is given by the function h(t)= -16t^2+ kt.
\n" ); document.write( " if the object returns to the ground at t=8 sec., find the height (in feet) of the object at t=7 sec.
\n" ); document.write( "Explain in words your steps to finding the value of k.
\n" ); document.write( ":
\n" ); document.write( "When it hits the ground h(t) = 0, when t = 8
\n" ); document.write( "-16(8^2) + 8k = 0
\n" ); document.write( "-16(64) + 8k = 0
\n" ); document.write( "-1024 + 8k
\n" ); document.write( "8k = 1024
\n" ); document.write( "k = 1024/8
\n" ); document.write( "k = 128
\n" ); document.write( "\"find the height when t = 7 sec
\n" ); document.write( "h(t) = -16(7^2) + 128(7)
\n" ); document.write( "h(t) = -784 + 896
\n" ); document.write( "h(t) = 112 ft, height at 7 sec \n" ); document.write( "
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