document.write( "Question 1042746: Use the Factor Theorem to determine whether x - c is a factor of f(x).\r
\n" ); document.write( "\n" ); document.write( "8x3 + 36x2 - 19x - 5; x + 5
\n" ); document.write( " a. Yes
\n" ); document.write( " b. No
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Algebra.Com's Answer #657774 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
x+5 is really x - (-5)\r
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\n" ); document.write( "\n" ); document.write( "x - (-5) is in the form x - c where c = -5 in this case.\r
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\n" ); document.write( "\n" ); document.write( "Remainder Theorem: if x - c is a factor of f(x), then f(c) = 0. This works both ways. If f(c) = 0, then x-c is a factor of f(x).\r
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\n" ); document.write( "\n" ); document.write( "Use the remainder theorem to see if plugging x = -5 into f(x) yields 0.\r
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\n" ); document.write( "\n" ); document.write( "y = 8x^3 +36x^2 - 19x - 5
\n" ); document.write( "y = 8(-5)^3 +36(-5)^2 - 19(-5) - 5
\n" ); document.write( "y = 8(-125) +36(25) - 19(-5) - 5
\n" ); document.write( "y = -1000 + 900 + 95 - 5
\n" ); document.write( "y = -100 + 95 - 5
\n" ); document.write( "y = -5 - 5
\n" ); document.write( "y = -10\r
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\n" ); document.write( "\n" ); document.write( "The result is -10 which is NOT zero. Since it's not zero, this means that x+5 is NOT a factor of f(x).\r
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\n" ); document.write( "\n" ); document.write( "Note: if you change y = 8x^3 +36x^2 - 19x - 5 to y = 8x^3 +36x^2 - 19x + 5, then x+5 would be a factor
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