document.write( "Question 178185: Question: When we multiply or divide on both sides by a negative number we must reverse the inequality symbol. I understand why this needs to be done. But why do we not have to do this when we are working with equations? Or do we do this with equations? \n" ); document.write( "

Algebra.Com's Answer #133195 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "If you reverse the inequality sign, you reverse the sense of the inequality. But you can't 'reverse' an equals sign. Equals is equals.\r
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\n" ); document.write( "\n" ); document.write( "Think about the reason that we reverse the inequality:\r
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2\"> is certainly a true statement, but multiplying by -1 gives us:\r
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-2\"> which is no longer true until you reverse the sign:

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\n" ); document.write( "\n" ); document.write( "But consider a statement containing equals:\r
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is true, and if you multiply by -1,

is still true.\r
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