document.write( "Question 92558This question is from textbook Algebra and Trigonometry
\n" ); document.write( ": Given that (3x-a)(x-2)(x-7)=3x cubed-32x squared+87x-70, determine the value of a. \n" ); document.write( "
Algebra.Com's Answer #67380 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "(3x - a)(x - 2)(x - 7) = 3x³ - 32x² + 87x - 70\r\n" );
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document.write( "It must be true for every value of x, so pick any\r\n" );
document.write( "value for x and substitute it.  The easiest value\r\n" );
document.write( "of x we can pick is 0, so let's substitute 0 for x:\r\n" );
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document.write( "(3·0 - a)(0 - 2)(0 - 7) = 3(0)³ - 32(0)² + 87(0) - 70\r\n" );
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document.write( "(-a)(-2)(-7) = -70\r\n" );
document.write( "        -14a = -70\r\n" );
document.write( "           a = \"%28-70%29%2F%28-14%29\"\r\n" );
document.write( "           a = 5\r\n" );
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document.write( "That's the answer.  But you could have picked ANY number\r\n" );
document.write( "to substitute for x.  For example I could even have picked\r\n" );
document.write( "a stupid number like 8\r\n" );
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document.write( " (3x - a)(x - 2)(x - 7) = 3x³ - 32x² + 87x - 70\r\n" );
document.write( "(3·8 - a)(8 - 2)(8 - 7) = 3(8)³ - 32(8)² + 87(8) - 70\r\n" );
document.write( "         (24 - a)(6)(1) = 3(512) - 32(64) + 696 - 70\r\n" );
document.write( "            (24 - a)(6) = 1536 - 2048 + 626\r\n" );
document.write( "              6(24 - a) = 114\r\n" );
document.write( "Divide both sides by 6\r\n" );
document.write( "                 24 - a = 19\r\n" );
document.write( "                     -a = 19-24\r\n" );
document.write( "                     -a = -5\r\n" );
document.write( "                      a = 5\r\n" );
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document.write( "Edwin

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