document.write( "Question 319776: Solve using the addition and multiplication principles.\r
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Algebra.Com's Answer #229009 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "-2(2y + 5) < -2(y - 9)\r\n" );
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document.write( "Solve it just like you would if there were an equal sign = instead\r\n" );
document.write( "of an inequality sign < until you get to the step when you divide or\r\n" );
document.write( "multiply both sides by something.   \r\n" );
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document.write( "Distribute to remove the parentheses:\r\n" );
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document.write( "-2(2y + 5) < -2(y - 9)\r\n" );
document.write( "  -4y - 10 < -2y\r\n" );
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document.write( "Add 2y to both sides to get the y-term off the right side:\r\n" );
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document.write( "  -4y - 10 < -2y\r\n" );
document.write( "  +2y        +2y\r\n" );
document.write( "  --------------\r\n" );
document.write( "  -2y - 10 <   0\r\n" );
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document.write( "Add +10 to both sides to get the term without a y off the left side:\r\n" );
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document.write( "   -2y - 10 <  0\r\n" );
document.write( "       + 10  +10\r\n" );
document.write( "   -------------\r\n" );
document.write( "   -2y      < 10\r\n" );
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document.write( "Now this is where solving inequalities are different from \r\n" );
document.write( "solving equations.  \r\n" );
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document.write( "If you divide or multiply both sides by a NEGATIVE number, you\r\n" );
document.write( "must change the direction (reverse) of the inequality.  So when \r\n" );
document.write( "we divide both sides of the above by -2, since -2 is a NEGATIVE \r\n" );
document.write( "number, we must change the < to >\r\n" );
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document.write( "        y > -10\r\n" );
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document.write( "Note:  It is just as important for other inequalities that you\r\n" );
document.write( "may have to solve, that you remember this:  When you divide or multiply\r\n" );
document.write( "both sides by a POSITIVE number you DO NOT reverse the inequality sign!  \r\n" );
document.write( "JUST DON'T get the idea that you always reverse the inequality sign.  \r\n" );
document.write( "You reverse it when but ONLY WHEN(!) you divide or multiply through by \r\n" );
document.write( "a NEGATIVE number.\r\n" );
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document.write( "To graph that solution on a number line:\r\n" );
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document.write( "------------o================================================================>\r\n" );
document.write( "-12  -11  -10   -9   -8   -7   -6   -5   -4   -3   -2   -1    0    1    2    3\r\n" );
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document.write( "The interval notation for this solution set is [-10,\"infinity\")\r\n" );
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document.write( "Edwin
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