document.write( "Question 499454: how to solve by substitution 4x+y=11;2x+5y=1 \n" ); document.write( "

Algebra.Com's Answer #337695 by oberobic(2304) $\"\"$ $\"About$

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4x+y=11
\n" ); document.write( "2x+5y = 1
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\n" ); document.write( "4x+y = 11
\n" ); document.write( "subtract 4x from both sides
\n" ); document.write( "y = -4x +11
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\n" ); document.write( "substitute that into the 2nd equation
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\n" ); document.write( "2x + 5(-4x + 11) = 1
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\n" ); document.write( "multiply through
\n" ); document.write( "2x -20x +55 = 1
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\n" ); document.write( "collect terms & subtract 55 from both sides
\n" ); document.write( "-18x = -54
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\n" ); document.write( "divide both sides by -18
\n" ); document.write( "x = -54/-18
\n" ); document.write( "x = 54/18
\n" ); document.write( "x = 3
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\n" ); document.write( "Now substitute that value to find 'y'
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\n" ); document.write( "4x+y=11
\n" ); document.write( "4(3) + y = 11
\n" ); document.write( "12 + y = 11
\n" ); document.write( "y = -1
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\n" ); document.write( "x = 3
\n" ); document.write( "y = -1
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