document.write( "Question 91996: /3x+2/= 14
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Algebra.Com's Answer #66822 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"abs%283x%2B2%29+=+14\"
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\n" ); document.write( "You are to solve for x. A way to do this is to take the quantity inside the absolute
\n" ); document.write( "value signs and precede it with plus and minus signs and solve it like an equation.
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\n" ); document.write( "In other words, the quantity inside the absolute value signs is (3x + 2). So you set up two
\n" ); document.write( "equations ... one using +(3x+2) and the other using -(3x+2).
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\n" ); document.write( "The first equation is:
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\n" ); document.write( "+(3x +2) = 14
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\n" ); document.write( "Since the parentheses are preceded by a plus sign, you can just remove them to get:
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\n" ); document.write( "3x + 2 = 14
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\n" ); document.write( "Get rid of the 2 on the left side by subtracting 2 from both sides to get:
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\n" ); document.write( "3x = 12
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\n" ); document.write( "Solve for x by dividing both sides by 3 and you get:
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\n" ); document.write( "x = 12/3 = 4
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\n" ); document.write( "So x = 4 is one of the answers.
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\n" ); document.write( "Now set up a second equation using minus the quantity inside the absolute value signs. This
\n" ); document.write( "equation becomes:
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\n" ); document.write( "-(3x + 2) = 14
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\n" ); document.write( "The minus sign in front of the parentheses tells you to change the sign of every term in
\n" ); document.write( "the parentheses if you wish to remove the parentheses. Therefore, when you remove the
\n" ); document.write( "parentheses this equation becomes:
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\n" ); document.write( "-3x - 2 = 14
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\n" ); document.write( "Get rid of the -2 on the left side by adding 2 to both sides. When you do the equation
\n" ); document.write( "becomes:
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\n" ); document.write( "-3x = 16
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\n" ); document.write( "Now solve for x by dividing both sides by -3. This division makes the equation become:
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\n" ); document.write( "x = -16/3
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\n" ); document.write( "So now you have the two answers: x = 4 and x = -16/3
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\n" ); document.write( "Let's check them out. The original equation was:
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\n" ); document.write( "\"abs%283x+%2B2%29+=+14\"
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\n" ); document.write( "Setting x equal to 4 results in:
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\n" ); document.write( "\"abs%28%283%2A4%29%2B2%29+=+14\"
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\n" ); document.write( "Multiplying inside the absolute value signs gives:
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\n" ); document.write( "\"abs%28%2812%29%2B2%29+=+14\"
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\n" ); document.write( "which simplifies to:
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\n" ); document.write( "\"abs%2814%29+=+14\"
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\n" ); document.write( "And since the absolute value of +14 is 14, this equation becomes:
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\n" ); document.write( "\"14+=+14\"
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\n" ); document.write( "which is true. Therefore, x = 4 is a good solution.
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\n" ); document.write( "Next let's check out the other answer x = -16/3.
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\n" ); document.write( "Begin with
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\n" ); document.write( "\"abs%283x+%2B2%29+=+14\"
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\n" ); document.write( "Substitute -16/3 for x and the equation becomes:
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\n" ); document.write( "\"abs%28%283%2A%28-16%2F3%29%29+%2B2%29+=+14\"
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\n" ); document.write( "Doing the multiplication inside the absolute value signs gives:
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\n" ); document.write( "\"abs%28%28-48%2F3%29+%2B+2%29+=+14\"
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\n" ); document.write( "and since \"-48%2F3+=+-16\" the equation simplifies to:
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\n" ); document.write( "\"abs%28-16%2B2%29+=+14\"
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\n" ); document.write( "The addition inside the absolute value signs results in -14 so the equation becomes:
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\n" ); document.write( "\"abs%28-14%29+=+14\"
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\n" ); document.write( "but the absolute value of -14 is 14, so the equation becomes:
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\n" ); document.write( "\"14+=+14\"
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\n" ); document.write( "and since this is true, the answer \"x+=+-16%2F3\" is also correct.
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\n" ); document.write( "Hope this shows you a way to solve absolute value equations of this type. Just take the
\n" ); document.write( "plus and minus quantities of the expression inside the absolute value signs and set up
\n" ); document.write( "two equations. Then solve them just as you would an ordinary equation. This will give
\n" ); document.write( "you the answers. And it is a good practice to check your answers as was done above.
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