document.write( "Question 150630: 7) The path of a falling object is given by the function where represents the initial velocity in ft/sec and represents the initial height in feet. Also, s represents the height in feet of the object at any time, t, which is measured in seconds.\r
\n" ); document.write( "\n" ); document.write( "a) If a rock is thrown upward with an initial velocity of 40 feet per second from the top of a 30-foot building, write the height (s) equation using this information.\r
\n" ); document.write( "\n" ); document.write( " Typing hint: Type t-squared as t^2\r
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\n" ); document.write( "\n" ); document.write( "b) How high is the rock after 2 seconds?
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\n" ); document.write( "\n" ); document.write( "c) After how many seconds will the graph reach maximum height? Show your work algebraically.
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\n" ); document.write( " Show your work here:
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\n" ); document.write( "\n" ); document.write( "d) What is the maximum height?
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\n" ); document.write( "I have tried numerous approaches but don't feel I have the right answer. If I use the #2 in place of x my solution comes out to s=46 which does not sound reasonable to me. Please help \n" ); document.write( "
Algebra.Com's Answer #110565 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The path of a falling object is given by the function where represents the initial velocity in ft/sec and represents the initial height in feet. Also, s represents the height in feet of the object at any time, t, which is measured in seconds.
\n" ); document.write( "a) If a rock is thrown upward with an initial velocity of 40 feet per second from the top of a 30-foot building, write the height (s) equation using this information.
\n" ); document.write( "Typing hint: Type t-squared as t^2
\n" ); document.write( "Answer:
\n" ); document.write( ":
\n" ); document.write( "The equation consists of three parts,
\n" ); document.write( "Gravity: -16t^2; negative because it's pulling down
\n" ); document.write( "Initial velocity: +40t; plus because it's thrown upward
\n" ); document.write( "Initial height: 30; from a 30 ft building
\n" ); document.write( ":
\n" ); document.write( "s(t) = -16t^2 + 40t + 30
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\n" ); document.write( ":
\n" ); document.write( "b) How high is the rock after 2 seconds?
\n" ); document.write( "Answer:
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\n" ); document.write( "Substitute 2 for t in the above equation:
\n" ); document.write( "h = -16(2^2) + 40(2) + 30
\n" ); document.write( "h = -64 + 80 + 30
\n" ); document.write( "h = +46 ft; so you're right!!
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\n" ); document.write( "c) After how many seconds will the graph reach maximum height? Show your work algebraically.
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\n" ); document.write( "The max height will occur at the axis of symmetry x = \"%28-b%29%2F%282a%29\"
\n" ); document.write( "In your equation a=-16 and b=40
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\n" ); document.write( "t = \"%28-40%29%2F%282%2A-16%29\"
\n" ); document.write( "t = \"%28-40%29%2F%28-32%29\"
\n" ); document.write( "t = 1.25 seconds it will be max height
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\n" ); document.write( "d) What is the maximum height?
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\n" ); document.write( "Substitute 1.25 for t and find the height
\n" ); document.write( "h = -16(1.25^2) + 40(1.25) + 30
\n" ); document.write( "h = -16(1.5625) + 50 + 30
\n" ); document.write( "h = -25
\n" ); document.write( "h = 55 ft is the max height \n" ); document.write( "
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