document.write( "Question 1102896: How do you find the polynomial whose graph goes through these points? \r
\n" ); document.write( "\n" ); document.write( "(2,10), (-1,-4), (0,2), and (1,-2).\r
\n" ); document.write( "\n" ); document.write( "Thanks
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Algebra.Com's Answer #717608 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "n points can be fitted with a polynomial of degree (n-1). With 4 given points, you need a polynomial of degree 3:
\n" ); document.write( "\"P%28x%29+=+ax%5E3%2Bbx%5E2%2Bcx%2Bd\"

\n" ); document.write( "Simply make 4 equations in the unknown coefficients a, b, c, and d using the coordinates of the given points.
\n" ); document.write( "(2,10) --> \"8a%2B4b%2B2c%2Bd+=+10\" [1]
\n" ); document.write( "(-1,-4) --> \"-a%2Bb-c%2Bd+=+-4\" [2]
\n" ); document.write( "(0,2) --> \"d+=+2\" [3]
\n" ); document.write( "(1,-2) --> \"a%2Bb%2Bc%2Bd+=+-2\" [4]

\n" ); document.write( "Use [3] to simplify the others:
\n" ); document.write( "\"8a%2B4b%2B2c+=+8\" [5]
\n" ); document.write( "\"-a%2Bb-c+=+-6\" [6]
\n" ); document.write( "\"a%2Bb%2Bc+=+-4\" [7]

\n" ); document.write( "Add [6] and [7] to solve for b:
\n" ); document.write( "\"2b+=+-10\"
\n" ); document.write( "\"b+=+-5\" [8]

\n" ); document.write( "Use [8] to simplify [5] and [7]:
\n" ); document.write( "\"8a-20%2B2c+=+8\"
\n" ); document.write( "\"8a%2B2c+=+28\"
\n" ); document.write( "\"4a%2Bc+=+14\" [9]
\n" ); document.write( "\"a-5%2Bc+=+-4\"
\n" ); document.write( "\"a%2Bc+=+1\" [10]

\n" ); document.write( "Solve [9] and [10] by elimination to solve for a and c:
\n" ); document.write( "\"3a+=+13\"
\n" ); document.write( "\"a+=+13%2F3\"
\n" ); document.write( "\"c+=+-10%2F3\"

\n" ); document.write( "The polynomial is
\n" ); document.write( "\"p%28x%29+=+%2813%2F3%29x%5E3-5x%5E2-%2810%2F3%29x%2B2\"

\n" ); document.write( "Here is the graph...\n" ); document.write( "\"graph%28200%2C400%2C-3%2C3%2C-5%2C11%2C%2813%2F3%29x%5E3-5x%5E2-%2810%2F3%29x%2B2%29\"
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