document.write( "Question 1178755: Use a system of linear equations to find the quadratic function
\n" ); document.write( "f(x) = ax2 + bx + c
\n" ); document.write( " that satisfies the given conditions. Solve the system using matrices.
\n" ); document.write( "f(1) = 9, f(2) = 10, f(3) = 9
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Algebra.Com's Answer #808157 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+ax%5E2+%2B+bx+%2B+c\"\r
\n" ); document.write( "\n" ); document.write( "that satisfies the given conditions. Solve the system using matrices.\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29+=+9\", \"f%282%29+=+10\", \"f%283%29+=+9\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+ax%5E2+%2B+bx+%2B+c\"..........if \"f%281%29+=+9\", \"x=1\",\"f%28x%29+=+9\"\r
\n" ); document.write( "\n" ); document.write( "\"9+=+a%2A1%5E2+%2B+b%2A1+%2B+c\"
\n" ); document.write( "\"+a+%2B+b+%2B+c=9\"..........eq.1\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+ax%5E2+%2B+bx+%2B+c\"..........if \"f%282%29+=10\", \"x=2\",\"f%28x%29+=+10\"\r
\n" ); document.write( "\n" ); document.write( "\"10+=+a%2A2%5E2+%2B+b%2A2+%2B+c\"
\n" ); document.write( "\"+4a+%2B+2b+%2B+c=10\"...................eq.2\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+ax%5E2+%2B+bx+%2B+c\"..........if \"f%283%29+=9\", \"x=3\",\"f%28x%29+=+9\"\r
\n" ); document.write( "\n" ); document.write( "\"9+=+a%2A3%5E2+%2B+b%2A3+%2B+c\"
\n" ); document.write( "\"+9a+%2B+3b+%2B+c=9\".................eq.3\r
\n" ); document.write( "\n" ); document.write( "your system is:\r
\n" ); document.write( "\n" ); document.write( "\"+a+%2B+b+%2B+c=9\"..........eq.1
\n" ); document.write( "\"+4a+%2B+2b+%2B+c=10\"...................eq.2
\n" ); document.write( "\"+9a+%2B+3b+%2B+c=9\".................eq.3
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\n" ); document.write( "\n" ); document.write( "Your matrix\r
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\n" ); document.write( "\n" ); document.write( "Find the pivot in the 1st column in the 1st row\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 1st column\r
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\n" ); document.write( "\n" ); document.write( "Make the pivot in the 2nd column by dividing the 2nd row by \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 2nd column\r
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\n" ); document.write( "\n" ); document.write( "Find the pivot in the 3rd column in the 3rd row\r
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\n" ); document.write( "\n" ); document.write( "Eliminate the 3rd column\r
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\n" ); document.write( "\n" ); document.write( "Solution set:
\n" ); document.write( "\"a=+-1\"
\n" ); document.write( "\"b+=+4\"
\n" ); document.write( "\"c+=+6\"\r
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\n" ); document.write( "\n" ); document.write( "and the quadratic function is:\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+-x%5E2+%2B+4x+%2B+6\"\r
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