document.write( "Question 771308: How to solve: 13= -3x - 8 \n" ); document.write( "

Algebra.Com's Answer #470110 by Edwin McCravy(20056) $\"\"$ $\"About$

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document.write( "   13 = -3x-8\r\n" );
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document.write( "We want terms with letters on the left and terms without letters on the right.\r\n" );
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document.write( "So we begin by getting rid of the 13 on the left, since 13 has no letter:\r\n" );
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document.write( "We add -13 to both sides:\r\n" );
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document.write( "   13 = -3x-8\r\n" );
document.write( "  -13      -13\r\n" );
document.write( "---------------\r\n" );
document.write( "    0 = -3x-21\r\n" );
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document.write( "Next we get rid of the -3x on the right since it has a letter:\r\n" );
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document.write( "We add 3x to both sides:\r\n" );
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document.write( "    0 = -3x-21\r\n" );
document.write( "   3x    3x\r\n" );
document.write( "---------------\r\n" );
document.write( "   3x =    -21\r\n" );
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document.write( "Finally we divide both sides by the coefficient of x\r\n" );
document.write( "which is 3:\r\n" );
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document.write( "    =    \r\n" );
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document.write( "Cancel the 3's on the left and divide on the right:\r\n" );
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document.write( "    =    -7\r\n" );
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document.write( "   x = -7\r\n" );
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document.write( "To check, substitute (-7) in place of x in the original equation:\r\n" );
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document.write( "    13 = -3x-8\r\n" );
document.write( "    13 = -3(-7)-8\r\n" );
document.write( "    13 = 21-8\r\n" );
document.write( "    13 = 13   <--- both sides equal so it is correct.\r\n" );
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document.write( "Edwin

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