document.write( "Question 179020: substitute,\r
\n" ); document.write( "\n" ); document.write( "x=2y+8
\n" ); document.write( "7x+y=101 \n" ); document.write( "

Algebra.Com's Answer #133969 by vleith(2983) $\"\"$ $\"About$

You can put this solution on YOUR website!
Given $\"x=2y%2B8\"$ and $\"7x%2By=101\"$
\n" ); document.write( "Use the value of x in the first equation and substitute it into the second equation
\n" ); document.write( " $\"7x%2By=101\"$
\n" ); document.write( " $\"7%282y%2B8%29%2By=101\"$
\n" ); document.write( " $\"14y+%2B+56+%2B+y+=+101\"$
\n" ); document.write( " $\"15y+%2B+56+=+101\"$
\n" ); document.write( " $\"15y+=+101+-+56\"$
\n" ); document.write( " $\"15y+=+45\"$
\n" ); document.write( " $\"y+=+45%2F15\"$
\n" ); document.write( " $\"y+=+3\"$ \r
\n" ); document.write( "\n" ); document.write( "Now take that value for y and substitute it into the first equation to solve for x
\n" ); document.write( " $\"x=+2y+%2B+8\"$
\n" ); document.write( " $\"x+=+2%283%29+%2B+8\"$
\n" ); document.write( " $\"x+=+6+%2B+8\"$
\n" ); document.write( " $\"x+=+14\"$ \r
\n" ); document.write( "\n" ); document.write( "Check your answer using equation 2
\n" ); document.write( "Does $\"7%2814%29+%2B+3+=+101\"$ ???
\n" ); document.write( " $\"98+%2B+3+=+101+\"$ ?
\n" ); document.write( "yes it does\r
\n" ); document.write( "\n" ); document.write( "so x = 14 and y = 3 \n" ); document.write( "

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