document.write( "Question 166070: 2[d + 3] = 8\r
\n" ); document.write( "\n" ); document.write( "The bar is a straight line, and I don't know how to type it. It is called the
\n" ); document.write( "absolute bar.\r
\n" ); document.write( "\n" ); document.write( "THanks for your help!
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Algebra.Com's Answer #122415 by midwood_trail(310)\"\" \"About 
You can put this solution on YOUR website!
To solve an absolute value equation, isolate the absolute value on one side of the equal sign, and establish two cases:\r
\n" ); document.write( "\n" ); document.write( "Case One:\r
\n" ); document.write( "\n" ); document.write( "Set the expression inside the
\n" ); document.write( "absolute value symbol equal to
\n" ); document.write( "the other given expression.\r
\n" ); document.write( "\n" ); document.write( "Case Two:\r
\n" ); document.write( "\n" ); document.write( "Set the expression inside the
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\n" ); document.write( "the negation of the other given
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\n" ); document.write( "\n" ); document.write( "Your question:\r
\n" ); document.write( "\n" ); document.write( "2|d + 3| = 8\r
\n" ); document.write( "\n" ); document.write( "We want to isolate the absolute value first.\r
\n" ); document.write( "\n" ); document.write( "We divide both sides by 2 to get this done.\r
\n" ); document.write( "\n" ); document.write( "|d + 3| = 8/2\r
\n" ); document.write( "\n" ); document.write( "|d + 3| = 4\r
\n" ); document.write( "\n" ); document.write( "We now establish two cases as written above.\r
\n" ); document.write( "\n" ); document.write( "Case One:\r
\n" ); document.write( "\n" ); document.write( "d + 3 = 4\r
\n" ); document.write( "\n" ); document.write( "d = 4 - 3\r
\n" ); document.write( "\n" ); document.write( "d = 1\r
\n" ); document.write( "\n" ); document.write( "Case Two:\r
\n" ); document.write( "\n" ); document.write( "d + 3 = -4\r
\n" ); document.write( "\n" ); document.write( "d = -4 - 3\r
\n" ); document.write( "\n" ); document.write( "d = -7\r
\n" ); document.write( "\n" ); document.write( "Now, you must check. The two cases create \"derived\" equations. These derived equations may not always be true equivalents to the original equation. Consequently, the roots of the derived equations MUST BE CHECKED in the original equation so that you do not list extraneous roots as answers.\r
\n" ); document.write( "\n" ); document.write( "We plug our answers of d = 1 and d = -7 in the original absolute value equation given to see which will create the same answer on both sides of the equation.\r
\n" ); document.write( "\n" ); document.write( "Let d = 1\r
\n" ); document.write( "\n" ); document.write( "2|1 + 3| = 8\r
\n" ); document.write( "\n" ); document.write( "2|4| = 8\r
\n" ); document.write( "\n" ); document.write( "2(4) = 8\r
\n" ); document.write( "\n" ); document.write( "8 = 8...It checks!!\r
\n" ); document.write( "\n" ); document.write( "We now let d = -7\r
\n" ); document.write( "\n" ); document.write( "2|-7 + 3| = 8\r
\n" ); document.write( "\n" ); document.write( "2|-4| = 8\r
\n" ); document.write( "\n" ); document.write( "2(4) = 8\r
\n" ); document.write( "\n" ); document.write( "8 = 8...It also checks!!\r
\n" ); document.write( "\n" ); document.write( "So, our final answer is: d = 1 and d = -7\r
\n" ); document.write( "\n" ); document.write( "Did you follow?\r
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