document.write( "Question 106053: If 12 is subtracted from three times a number and the difference is multiplied by 2, the result is -42. Find the number. \n" ); document.write( "

Algebra.Com's Answer #77152 by MathLover1(20850) $\"\"$ $\"About$

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If $\"12\"$ is subtracted from three times a number, we can write it as
\n" ); document.write( " $\"3x-12\"$ \r
\n" ); document.write( "\n" ); document.write( "and the difference is multiplied by $\"2\"$ , we can write it as\r
\n" ); document.write( "\n" ); document.write( " $\"%283x-12%292\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "and if the result is $\"-42\"$ ,we can write it as\r
\n" ); document.write( "\n" ); document.write( " $\"%283x-12%292+=+-42\"$ \r
\n" ); document.write( "\n" ); document.write( " Find the number:\r
\n" ); document.write( "\n" ); document.write( " $\"%283x-12%292+=+-42\"$ ---- both sides divide by $\"2\"$
\n" ); document.write( " $\"3x+-+12+=+-21\"$ ---- add $\"%2B12\"$ to both sides\r
\n" ); document.write( "\n" ); document.write( " $\"3x+-+12+%2B+12+=+-21+%2B+12\"$ \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"3x+=+-9\"$ ---- both sides divide by $\"3\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"x+=+-3\"$ \r
\n" ); document.write( "\n" ); document.write( "check:\r
\n" ); document.write( "\n" ); document.write( " $\"%283x-12%292+=+-42\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"%283%2A%28-3%29+-12%292+=+-+42\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"%28-9+-12%292+=+42\"$
\n" ); document.write( " $\"-21%2A2+=+-42\"$
\n" ); document.write( " $\"-42+=+-42\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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