document.write( "Question 1193296: 2|3x-4|-3|2x+1|<7
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Algebra.Com's Answer #825313 by greenestamps(13200)\"\" \"About 
You can put this solution on YOUR website!


\n" ); document.write( "The behavior of the absolute value function changes at the two points where the absolute value expressions are equal to 0.

\n" ); document.write( "3x-4=0 --> x=4/3
\n" ); document.write( "2x+1=0 --> x=-1/2

\n" ); document.write( "Those two values of x divide the domain into three intervals: x less than -1/2, x between -1/2 and 4/3, and x greater than 4/3. Look for solutions in each of those intervals.

\n" ); document.write( "(1) x less than -1/2....

\n" ); document.write( "On this interval, \"abs%283x-4%29=-3x%2B4\" and \"abs%282x%2B1%29=-2x-1\"

\n" ); document.write( "\"2%28-3x%2B4%29-3%28-2x-1%29%3C7\"
\n" ); document.write( "\"-6x%2B8%2B6x%2B3%3C7\"
\n" ); document.write( "\"11%3C7\"

\n" ); document.write( "That inequality is clearly never true; so there are no solutions in this interval.

\n" ); document.write( "(2) x between -1/2 and 4/3....

\n" ); document.write( "On this interval, \"abs%283x-4%29=-3x%2B4\" and \"abs%282x%2B1%29=2x%2B1\"

\n" ); document.write( "\"2%28-3x%2B4%29-3%282x%2B1%29%3C7\"
\n" ); document.write( "\"-6x%2B8-6x-3%3C7\"
\n" ); document.write( "\"-12x%2B5%3C7\"
\n" ); document.write( "\"-2%3C12x\"
\n" ); document.write( "\"x%3E-1%2F6\"

\n" ); document.write( "x=-1/6 is in this interval, so part of the solution set is x between -1/6 and x=4/3

\n" ); document.write( "(3) x greater than 4/3....

\n" ); document.write( "On this interval, \"abs%283x-4%29=3x-4\" and \"abs%282x%2B1%29=2x%2B1\"

\n" ); document.write( "\"2%283x-4%29-3%282x%2B1%29%3C7\"
\n" ); document.write( "\"6x-8-6x-3%3C7\"
\n" ); document.write( "\"-11%3C7\"

\n" ); document.write( "That inequality is always true, so the entire interval x greater than 4/3 is part of the solution set.

\n" ); document.write( "ANSWER: The solution set is (-1/6,infinity)

\n" ); document.write( "A graph confirms that answer:

\n" ); document.write( "\"graph%28400%2C400%2C-3%2C3%2C-15%2C15%2C2%2Aabs%283x-4%29-3%2Aabs%282x%2B1%29%2C7%29\"

\n" ); document.write( "The value of the absolute value function (red) is less than 7 (green) everywhere to the right of x=-1/6.

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