document.write( "Question 728071: bronze which costs $9.10/kg is made by combining copper which costs $8.90/kg with tin which costs $9.50/kg. Find the number of kg of copper required to make 16.6 kg of bronze? \n" ); document.write( "

Algebra.Com's Answer #445299 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+a+\"$ = kg of copper needed
\n" ); document.write( "Let $\"+b+\"$ = kg of tin needed
\n" ); document.write( "(1) $\"+8.9a+%2B+9.5b+=+9.1%2A16.6+\"$
\n" ); document.write( "(2) $\"+a+%2B+b+=+16.6+\"$
\n" ); document.write( "------------------
\n" ); document.write( "(1) $\"+890a+%2B+950b+=+15106+\"$
\n" ); document.write( "Multiply both sides of (2) by $\"+890+\"$
\n" ); document.write( "and subtract (2) from (1)
\n" ); document.write( "(1) $\"+890a+%2B+950b+=+15106+\"$
\n" ); document.write( "(2) $\"+-890a+-+890b+=+-14774+\"$
\n" ); document.write( " $\"+60b+=+332+\"$
\n" ); document.write( " $\"+b+=+5.5333+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+a+%2B+b+=+16.6+\"$
\n" ); document.write( "(2) $\"+a+%2B+5.5333+=+16.6+\"$
\n" ); document.write( "(2) $\"+a+=+11.0667+\"$
\n" ); document.write( "11.0667 kg of copper is needed
\n" ); document.write( "5.5333 kg of tin is needed
\n" ); document.write( "check answer:
\n" ); document.write( "(1) $\"+8.9a+%2B+9.5b+=+9.1%2A16.6+\"$
\n" ); document.write( "(1) $\"+8.9%2A11.0667+%2B+9.5%2A5.5333+=+151.06+\"$
\n" ); document.write( "(1) $\"+98.49363+%2B+52.56635+=+151.06+\"$
\n" ); document.write( "(1) $\"+151.05998+=+151.06+\"$
\n" ); document.write( "close enough\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );