document.write( "Question 171023: Hi! I need to determine the equation of a parabola in the form y-k=a(x-h)^2\r
\n" ); document.write( "\n" ); document.write( "I am given 2 points on the graph (0,6) and (14,0)
\n" ); document.write( "I am given Part of V (9,k)\r
\n" ); document.write( "\n" ); document.write( "I have tried so many things, but nothing is even close to what it should be and I am ending up just writing the question over and over and now I am fully frustrated. I know I have to use both points given in order to get \"a\" and \"k\" and I probably have to substitute or eliminate but with two unknowns I have no idea how to go about it!
\n" ); document.write( "Any help would be seriously appreciated!
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Algebra.Com's Answer #126735 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
determine the equation of a parabola in the form y-k=a(x-h)^2
\n" ); document.write( "I am given 2 points on the graph (0,6) and (14,0)
\n" ); document.write( "I am given Part of V (9,k); I assume this means h=9
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\n" ); document.write( "Two equations:
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\n" ); document.write( "0,6:
\n" ); document.write( "6 - k = a(0 - 9)^2
\n" ); document.write( "6 - k = 81a
\n" ); document.write( "or
\n" ); document.write( "81a + k = 6
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\n" ); document.write( "14, 0
\n" ); document.write( "0 - k = a(14-9)^2
\n" ); document.write( "0 - k = a(5)^2
\n" ); document.write( "25a + k = 0
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\n" ); document.write( "Eliminate k, find a
\n" ); document.write( "81a + k = 6
\n" ); document.write( "24a + k = 0
\n" ); document.write( "-------------subtraction eliminates k
\n" ); document.write( "56a = 6
\n" ); document.write( "a = \"6%2F56\"
\n" ); document.write( "a = \"3%2F28\"
\n" ); document.write( ":
\n" ); document.write( "Find k using 25a + k = 0
\n" ); document.write( "25*(\"3%2F28\") + k = 0
\n" ); document.write( "\"75%2F28\" + k = 0
\n" ); document.write( "k = \"-75%2F28\"
\n" ); document.write( ":
\n" ); document.write( "The equation:
\n" ); document.write( "y = \"3%2F28\"(x - 9)^2 - \"75%2F28\"
\n" ); document.write( ":
\n" ); document.write( "Plots this:
\n" ); document.write( "
\n" ); document.write( ":
\n" ); document.write( "Looks about right
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