document.write( "Question 313617: x+y=56, 3x+y=56, how do I solve this by substition? Please Help \n" ); document.write( "

Algebra.Com's Answer #224230 by OmniMaestra(21) $\"\"$ $\"About$

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x+y=56, 3x+y=56,\r
\n" ); document.write( "\n" ); document.write( "Choose one of the equations and solve for one variable.\r
\n" ); document.write( "\n" ); document.write( "I'm going to solve the first equation for y.\r
\n" ); document.write( "\n" ); document.write( "subtract x from both sides:\r
\n" ); document.write( "\n" ); document.write( "y=56-x\r
\n" ); document.write( "\n" ); document.write( "Now use this value for y--->(56-x) and\r
\n" ); document.write( "\n" ); document.write( "substitute it into the other equation:\r
\n" ); document.write( "\n" ); document.write( "3x+(56-x)=56\r
\n" ); document.write( "\n" ); document.write( "solve for x. Combine like terms.\r
\n" ); document.write( "\n" ); document.write( "2x +56 = 56\r
\n" ); document.write( "\n" ); document.write( "subtract 56 from both sides.
\n" ); document.write( "2x = 0
\n" ); document.write( "divide by 2:
\n" ); document.write( "x=0\r
\n" ); document.write( "\n" ); document.write( "Now use one of the original equations and replace x with zero:\r
\n" ); document.write( "\n" ); document.write( "0+y=56\r
\n" ); document.write( "\n" ); document.write( "and solve for y:
\n" ); document.write( "y=56\r
\n" ); document.write( "\n" ); document.write( "The answer is, x=0 and y=56 \n" ); document.write( "

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