document.write( "Question 290094: What is the inherent meaning and justification of cross-multiplication as it applies to solving an inequality? \n" ); document.write( "
Algebra.Com's Answer #209952 by richwmiller(17219)\"\" \"About 
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Cross multiplication used to be frowned on by teachers because you aren't obviously doing the same thing to both sides.\r
\n" ); document.write( "\n" ); document.write( "3/4=x/7
\n" ); document.write( "The proper way is to
\n" ); document.write( "multiply both sides by 4
\n" ); document.write( "3*4/4=x*4/7
\n" ); document.write( "3=4x/7
\n" ); document.write( "then multiply both sides by 7
\n" ); document.write( "3*7=4x*7/7
\n" ); document.write( "simplify
\n" ); document.write( "3*7=4x
\n" ); document.write( "but with cross multiplication we skip the step of showing that we multiply one side by each number.
\n" ); document.write( "3/4=x/7
\n" ); document.write( "we jump right to the result
\n" ); document.write( "3*7=4x
\n" ); document.write( "It is shorter and therefore preferred by students.
\n" ); document.write( "However there is more chance of errors and not really understanding what you are doing and why.\r
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