document.write( "Question 1170225: the binomial (x+4) is a factor of the following polynomials, find the value of k.
\n" ); document.write( "1.2x^3-3x^2-kx+60
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\n" ); document.write( "\n" ); document.write( "Find the values of A, B and C if (x-1),(x+2), and (x-2) are factors of
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Algebra.Com's Answer #795082 by ikleyn(52786)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "In problems 1 - 5 below,  the idea of the solution is the same.\r
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\n" ); document.write( "\n" ); document.write( "You substitute the value of the root  x= -4  into the formula and equate this expression to zero.\r
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\n" ); document.write( "\n" ); document.write( "It gives you an equation to find  \"k\".\r
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\n" ); document.write( "\n" ); document.write( "Having this idea explained to you,  you can complete the rest on your own.\r
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\n" ); document.write( "\n" ); document.write( "Comment from student: what can you answer number 1 so I know what to do to others?\r
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\n" ); document.write( "\n" ); document.write( "My response :\r
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\n" ); document.write( "\n" ); document.write( "            It is  REALLY  GOOD  IDEA  start working with one specific case,  instead of posting  5  same type problems in one post.\r
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document.write( "1.  the binomial (x+4) is a factor of the following polynomials, find the value of k.\r\n" );
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document.write( "    2x^3 - 3x^2 - kx + 60\r\n" );
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document.write( "Since (x+4) is the root of the given polynomial, it means, due to the Remainder Theorem,\r\n" );
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document.write( "that (-4) is the root of the polynomial.\r\n" );
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document.write( "So, we substitute x= -4 into the polynomial and equate this expression to zero (since -4 is the root (!) )\r\n" );
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document.write( "We get then\r\n" );
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document.write( "    2*(-4)^3 - 3*(-4)^2 - k*(-4) + 60 = 0.\r\n" );
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document.write( "It is our BASIC EQUATION to find the unknown value of \"k\" :\r\n" );
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document.write( "   2*(-64) - 3*(16) - k*(-4) + 60 = 0\r\n" );
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document.write( "   -128    - 48     + 4k     + 60 = 0\r\n" );
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document.write( "   -116             + 4k          = 0\r\n" );
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document.write( "                      4k          = 116.\r\n" );
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document.write( "                       k          = 116/4 = 29.    \r\n" );
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document.write( "ANSWER.  k = 29.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Do other cases IN THE SAME WAY.\r
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\n" ); document.write( "\n" ); document.write( "It is a good problem,  and it is my pleasure to teach you.\r
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\n" ); document.write( "\n" ); document.write( "Do you understand everything in my solution ?\r
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\n" ); document.write( "\n" ); document.write( "If you have questions,  do not hesitate to post them to me.\r
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\n" ); document.write( "\n" ); document.write( "Never submit many problems/questions of the same type in one post.\r
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\n" ); document.write( "\n" ); document.write( "It is really irritates tutors; works against you and creates bad impression about a visitor.\r
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\n" ); document.write( "\n" ); document.write( "By the way,  it is  PROHIBITED  by the rules of this forum.\r
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\n" ); document.write( "\n" ); document.write( "Happy learning  (!)\r
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\n" ); document.write( "\n" ); document.write( "   Theorem   (the remainder theorem)\r
\n" ); document.write( "\n" ); document.write( "   1. The remainder of division the polynomial  \"f%28x%29\"  by the binomial  \"x-a\"  is equal to the value  \"f%28a%29\"  of the polynomial. \r
\n" ); document.write( "\n" ); document.write( "   2. The binomial  \"x-a\"  divides the polynomial  \"f%28x%29\"  if and only if the value of  \"a\"  is the root of the polynomial  \"f%28x%29\",  i.e.  \"f%28a%29+=+0\".\r
\n" ); document.write( "\n" ); document.write( "   3. The binomial  \"x-a\"  factors the polynomial  \"f%28x%29\"  if and only if the value of  \"a\"  is the root of the polynomial  \"f%28x%29\",  i.e.  \"f%28a%29+=+0\".\r
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\n" ); document.write( "\n" ); document.write( "See the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Divisibility of polynomial f(x) by binomial x-a and the Remainder theorem\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on the Remainder thoerem\r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic
\n" ); document.write( "\"Divisibility of polynomial f(x) by binomial (x-a). The Remainder theorem\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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