document.write( "Question 1122638: The slope of the tangent line to the graph of a cubic polynomial is -24 at two different points: (-2,79) and (1,-20). Determine the equation of the cubic polynomial. \n" ); document.write( "
Algebra.Com's Answer #738795 by josmiceli(19441)\"\" \"About 
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Express the polynomial as:
\n" ); document.write( "\"+a%2Ax%5E3+%2B+b%2Ax%5E2+%2B+c%2Ax+%2B+d+\"
\n" ); document.write( "The slope at any point is
\n" ); document.write( "\"+a%2Ax%5E2+%2B+b%2Ax+%2B+c+\"
\n" ); document.write( "——————————-
\n" ); document.write( "( -2, 79 )
\n" ); document.write( "\"+a%2A%28-2%29%5E2+%2B+b%2A%28-2%29+%2B+c+=+-24+\"
\n" ); document.write( "\"+4a+-+b+%2B+c+=+-24+\"
\n" ); document.write( "and
\n" ); document.write( "\"+a%2A%28-2%29%5E3+%2B+b%2A%28-2%29%5E2+%2Bc%2A%28-2%29+%2B+d+=+79+\"
\n" ); document.write( "\"+-8a+%2B+4b+-+2c+%2B+d+=+79+\"
\n" ); document.write( "———————————————-
\n" ); document.write( "(1,-20)
\n" ); document.write( "\"+a%2A1%5E2+%2B+b%2A1+%2B+c+=+-24+\"
\n" ); document.write( "\"+a+%2B+b+%2B+c+=+-24+\"
\n" ); document.write( "and
\n" ); document.write( "\"+a%2A1%5E3+%2B+b%2A1%5E2+%2B+c%2A1+%2B+d+=+-20+\"
\n" ); document.write( "\"+a+%2B+b+%2B+c+%2B+d+=+-20+\"
\n" ); document.write( "—————————
\n" ); document.write( "You have 4 equations with 4 unknowns,
\n" ); document.write( "So solve by any means you want\r
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