document.write( "Question 503728: Please help, thank you :)
\n" ); document.write( "The monthly value of a share of ACME Corporation, in dollars, since January 2009 are shown in the table below. The values of the table below model the behavior of a quadratic function when it is graphed.\r
\n" ); document.write( "\n" ); document.write( "Month.......... Share Value (in dollars)
\n" ); document.write( "0...... 55
\n" ); document.write( "3...... 16
\n" ); document.write( "5...... 0
\n" ); document.write( "7...... -8
\n" ); document.write( "9..... -8
\n" ); document.write( "11.... 0
\n" ); document.write( "13.... 16
\n" ); document.write( "15..... 40\r
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\n" ); document.write( "\n" ); document.write( "1. Using the table above, find the quadratic equation that represents the monthly value of a share of ACME Corporation since January 2009. Use the variable x to represent the number of months after January 2009 and the variable y to represent the monthly value.
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\n" ); document.write( "Answer Box (Type your work and answer below)
\n" ); document.write( "Hint: Two row values of the table represent the roots of the quadratic equation. Use these values to find the equation \r
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\n" ); document.write( "\n" ); document.write( "2. Find the y-intercept. Interpret the meaning of the y-intercept in relation to the given real-life scenario.
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\n" ); document.write( "Answer Box (Type your work and answer below)
\n" ); document.write( "Hint: The y intercept is when the graph intersects the y-axis.\r
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\n" ); document.write( "\n" ); document.write( "3. Find the x-intercepts. Interpret the meaning of the x-intercepts in relation to the given real-life scenario.\r
\n" ); document.write( "\n" ); document.write( "Answer Box (Type your work and answer below)
\n" ); document.write( "Hint: The x intercept is when the graph intersects the x-axis.\r
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\n" ); document.write( "\n" ); document.write( "4. From the equation you found in problem 1, what is the concavity of the parabola? How do you know? What is the lowest or maximum monthly value of a share of ACME Corporation and when did that occur?\r
\n" ); document.write( "\n" ); document.write( "Answer Box (Type your work and answer below)
\n" ); document.write( "Hint: Find the vertex of the parabola. Remember x represents the number of months since January 2009.\r
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\n" ); document.write( "5. Using the quadratic equation you found in problem 1, predict the value of a share of ACME Corporation in October 2010?\r
\n" ); document.write( "\n" ); document.write( "Answer Box (Type your work and answer below)
\n" ); document.write( "Hint: Remember x represents the number of months since January 2009.
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Algebra.Com's Answer #339435 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The monthly value of a share of ACME Corporation, in dollars, since January 2009 are shown in the table below. The values of the table below model the behavior of a quadratic function when it is graphed.
\n" ); document.write( "Month.......... Share Value (in dollars)
\n" ); document.write( "0...... 55
\n" ); document.write( "3...... 16
\n" ); document.write( "5...... 0
\n" ); document.write( "7...... -8
\n" ); document.write( "9..... -8
\n" ); document.write( "11.... 0
\n" ); document.write( "13.... 16
\n" ); document.write( "15..... 40\r
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\n" ); document.write( "\n" ); document.write( "1. Using the table above, find the quadratic equation that represents the monthly value of a share of ACME Corporation since January 2009. Use the variable x to represent the number of months after January 2009 and the variable y to represent the monthly value.
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\n" ); document.write( "Note that when x = 5 and x = 11, y = 0, therefore these are the x intercepts
\n" ); document.write( "(as the hint says); derive two factors and use FOIL to create a quadratic equation
\n" ); document.write( "(x-5)*(x-11) = x^2 - 11x - 5x + 55
\n" ); document.write( "y = x^2 - 16x + 55; is the equation
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\n" ); document.write( "2. Find the y-intercept. Interpret the meaning of the y-intercept in relation to the given real-life scenario.
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\n" ); document.write( "The y intercept occurs when x = 0, then y = 55
\n" ); document.write( "This would be the initial value in Jan 2009
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\n" ); document.write( "3. Find the x-intercepts. Interpret the meaning of the x-intercepts in relation to the given real-life scenario.
\n" ); document.write( "From this we have to assume the share value was par (0) in March and June
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\n" ); document.write( "4. From the equation you found in problem 1, what is the concavity of the parabola? How do you know? What is the lowest or maximum monthly value of a share of ACME Corporation and when did that occur?
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\n" ); document.write( "we know from the fact that the coefficient of x^2 is positive, it is concave and has a minimum
\n" ); document.write( "Here is a graph of that equation, you can see for yourself
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+20%2C+-30%2C+80%2C+x%5E2-16x%2B55%29+\"
\n" ); document.write( "you can see that the min value is in Aug, (x=8), when the value is -9
\n" ); document.write( "which is the vertex, 8,-9
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\n" ); document.write( "5. Using the quadratic equation you found in problem 1, predict the value of a share of ACME Corporation in October 2010?
\n" ); document.write( "Oct 2010, x = 22
\n" ); document.write( ":
\n" ); document.write( "y = x^2 - 16x + 55
\n" ); document.write( "y = 22^2 - 16(22) + 55
\n" ); document.write( "y = 484 - 352 + 55
\n" ); document.write( "y = 187 in Oct 2010
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\n" ); document.write( "redraw our graph to show this
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+30%2C+-100%2C+220%2C+x%5E2-16x%2B55%29+\"
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