document.write( "Question 189152: I would appreciate it if you can help me this is a Quadratic function question.\r
\n" ); document.write( "\n" ); document.write( "I would try to begin but I have no idea on how to start.\r
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\n" ); document.write( "\n" ); document.write( "1) A ball is thrown upward with an initial velocity of 32 ft./sec from a height of six ft.
\n" ); document.write( "The function s(t)=-16t*+32t+6 gives the height of the ball t seconds after release. Determine the time when the ball is at maximum height, and find that height.\r
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\n" ); document.write( "\n" ); document.write( "2) Jessica can be paid one of two ways for painting a house:
\n" ); document.write( "Plan A: $200 plus $12 per hour
\n" ); document.write( "Plan B: $20 per hour
\n" ); document.write( "Suppose the job takes n hours to complete. For what values of n is Plan A better for Jessica? \r
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\n" ); document.write( "\n" ); document.write( "3) In a study, it was found that the threshold weight, W, defined as the weight above which the risk of death rises dramatically, is given by
\n" ); document.write( "W(h)=( h/12.3) cube
\n" ); document.write( "Find the threshold weight for someone 5 ft 7 inches tall.\r
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\n" ); document.write( "\n" ); document.write( "Thank you for your help! \n" ); document.write( "
Algebra.Com's Answer #141903 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
1) A ball is thrown upward with an initial velocity of 32 ft./sec from a height of six ft.
\n" ); document.write( "The function s(t)=-16t*+32t+6 gives the height of the ball t seconds after release. Determine the time when the ball is at maximum height, and find that height.
\n" ); document.write( "Method 1:
\n" ); document.write( "Set the 1st derivate = 0.
\n" ); document.write( "-32t + 32 = 0
\n" ); document.write( "t = 1 second
\n" ); document.write( "s(1) = -16 + 32 + 6
\n" ); document.write( "max = 22 feet
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\n" ); document.write( "Method 2:
\n" ); document.write( "pick a height, eg, the starting height of 6 feet and set it equal to that.
\n" ); document.write( "-16t^2 + 32t + 6 = 6
\n" ); document.write( "16t^2 = 32t
\n" ); document.write( "t = 0, t = 2
\n" ); document.write( "These are the 2 times that the ball is at 6 feet. The center time, 1 sec, is the time the ball is at its max.
\n" ); document.write( "(0+2)/2 = 1 second, same answer.
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\n" ); document.write( "I'll do the others later.
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\n" ); document.write( "2) Jessica can be paid one of two ways for painting a house:
\n" ); document.write( "Plan A: $200 plus $12 per hour
\n" ); document.write( "Plan B: $20 per hour
\n" ); document.write( "Suppose the job takes n hours to complete. For what values of n is Plan A better for Jessica? \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "3) In a study, it was found that the threshold weight, W, defined as the weight above which the risk of death rises dramatically, is given by
\n" ); document.write( "W(h)=( h/12.3) cube
\n" ); document.write( "Find the threshold weight for someone 5 ft 7 inches tall.
\n" ); document.write( "Is h in inches?
\n" ); document.write( "W(67) = (67/12.3)^3
\n" ); document.write( "= 161.6 (is that pounds?)
\n" ); document.write( "You need to specify units.
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