document.write( "Question 1025047: A shop has 48 notebooks for sale. The number of blue notebook is 12 less than twice the number of red notebooks. How many blue notebooks are there?
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Algebra.Com's Answer #640341 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = number of blue notebooks
\n" ); document.write( "Let $\"+b+\"$ = number of red notebooks
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\n" ); document.write( "(1) $\"+a+%2B+b+=+48+\"$
\n" ); document.write( "(2) $\"+a+=+2b+-+12+\"$
\n" ); document.write( "------------------
\n" ); document.write( "Substitute (2) into (1)
\n" ); document.write( "(1) $\"+2b+-+12+%2B+b+=+48+\"$
\n" ); document.write( "(1) $\"+3b+=+60+\"$
\n" ); document.write( "(1) $\"+b+=+20+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+a+=+2b+-+12+\"$
\n" ); document.write( "(2) $\"+a+=+2%2A20-+12+\"$
\n" ); document.write( "(2) $\"+a+=+40+-+12+\"$
\n" ); document.write( "(2) $\"+a+=+28+\"$
\n" ); document.write( "---------------
\n" ); document.write( "There are 28 blue notebooks
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\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+a+=+2b+-+12+\"$
\n" ); document.write( "(2) $\"+28+=+2%2A20+-+12+\"$
\n" ); document.write( "(2) $\"+28+=+40+-+12+\"$
\n" ); document.write( "(2) $\"+28+=+28+\"$
\n" ); document.write( "OK \n" ); document.write( "

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