document.write( "Question 1063017: Find a polynomial function whose graph passes through each set of points. (-2,10) (-1,-4) (0,-2) (1,-2) \n" ); document.write( "
Algebra.Com's Answer #678042 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
Four points could go well for degree-three polynomial function.
\n" ); document.write( "Unknown constant coefficients, a, b, c, d;
\n" ); document.write( "\"ax%5E3%2Bbx%5E2%2Bcx%2Bd=y\"\r
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\n" ); document.write( "\n" ); document.write( "Use the given points to form four specific degree-three equations for a system.
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\n" ); document.write( "\n" ); document.write( "\"system%28-8a%2B4b-2c%2Bd=10%2C-a%2Bb-c%2Bd=-4%2Cd=-2%2Ca%2Bb%2Bc%2Bd=-2%29\"
\n" ); document.write( "This is the system to solve.\r
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\n" ); document.write( "\n" ); document.write( "Substituting for d makes for a simpler three-variable system
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\n" ); document.write( "\n" ); document.write( "(-1/2)*E1 gives
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\n" ); document.write( "\n" ); document.write( "E1-E3 and E2-E3 give
\n" ); document.write( "\"system%283a-3b=-6%2C-2b=2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"system%28a-b=-2%2Cb=-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "This very simple system gives two of the variables.
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\n" ); document.write( "\n" ); document.write( "d was already found early, and with a, b, d, all now found, c can be evaluated, whichever equation you want.\r
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