document.write( "Question 314756: substitution on linear equations.
\n" ); document.write( "4x-5y=20 and 5x+5y=70 \n" ); document.write( "

Algebra.Com's Answer #225181 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
1. $\"4x-5y=20\"$
\n" ); document.write( "2. $\"5x%2B5y=70\"$
\n" ); document.write( "From eq. 2,
\n" ); document.write( " $\"5y=70-5x\"$
\n" ); document.write( "Substitute into eq. 1,
\n" ); document.write( " $\"4x-%2870-5x%29=20\"$
\n" ); document.write( " $\"4x-70%2B5x=20\"$
\n" ); document.write( " $\"9x=90\"$
\n" ); document.write( " $\"highlight%28+x=10%29\"$
\n" ); document.write( "Then,
\n" ); document.write( " $\"5y=70-5x\"$
\n" ); document.write( " $\"5y=70-50\"$
\n" ); document.write( " $\"5y=20\"$
\n" ); document.write( " $\"highlight%28y=4%29\"$ \n" ); document.write( "

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