document.write( "Question 26350: Kina solved -15q<135 by adding 15 to each side of the inequality. What mistake did she make?
\n" ); document.write( "B. kina's solution was q<150. She checked her work by substituting 150 for q in the original inequality. Why didn’t her check let her know that she had made a mistake?
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Algebra.Com's Answer #14208 by Earlsdon(6294) $\"\"$ $\"About$

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First, Kina tried to add un-like terms (-15q+15) does not equal q, it equals (-15q+15). When she used 150 to check her solution, it would appear to have checked out because she would have ended up with: -2250<135 and this is true.
\n" ); document.write( "What Kina should have done is divide both sides of the inequality by -15 and, in doing this, she also should have reversed the order of the inequality.\r
\n" ); document.write( "\n" ); document.write( " $\"-15q+%3C+135\"$ Divide both sides by -15 and reverse the order of the inequality.
\n" ); document.write( " $\"q+%3E+-9\"$ \r
\n" ); document.write( "\n" ); document.write( "To check her solution, Kina should try a number that is greater than -9 because her solution is the set of all numbers greater than -9.\r
\n" ); document.write( "\n" ); document.write( "Try -5:
\n" ); document.write( " $\"-15%28-5%29+=+75\"$
\n" ); document.write( " $\"75+%3C+135\"$ It checks! \n" ); document.write( "

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