document.write( "Question 1019854: Use the substitution method to solve the following system of equations. And check your answers.\r
\n" ); document.write( "\n" ); document.write( "(1) 3x - y = 9
\n" ); document.write( "(2) 3y + 11 = 5x \n" ); document.write( "
Algebra.Com's Answer #635785 by Cromlix(4381)\"\" \"About 
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Hi there,
\n" ); document.write( "(1) 3x - y = 9
\n" ); document.write( "(2) 3y + 11 = 5x
\n" ); document.write( "Alter equation (1)
\n" ); document.write( "3x - y = 9
\n" ); document.write( "-y = 9 - 3x
\n" ); document.write( "y = 3x - 9
\n" ); document.write( "Substitute into Eq.(2)
\n" ); document.write( "3y + 11 = 5x
\n" ); document.write( "3(3x - 9) + 11 = 5x
\n" ); document.write( "9x - 27 + 11 = 5x
\n" ); document.write( "collect like terms
\n" ); document.write( "9x - 5x = 27 - 11
\n" ); document.write( "4x = 16
\n" ); document.write( "x = 4
\n" ); document.write( "Substitute x = 4 into (1)
\n" ); document.write( "3x - y = 9
\n" ); document.write( "3(4) - y = 9
\n" ); document.write( "12 - y = 9
\n" ); document.write( "-y = 9 - 12
\n" ); document.write( "-y = -3
\n" ); document.write( "y = 3
\n" ); document.write( "{4,3}
\n" ); document.write( "(1) 3x - y = 9
\n" ); document.write( " 3(4) - 3 = 9
\n" ); document.write( " 12 - 3 = 9
\n" ); document.write( " 9 = 9
\n" ); document.write( "(2) 3y + 11 = 5x
\n" ); document.write( " 3(3) + 11 = 5(4)
\n" ); document.write( " 9 + 11 = 20
\n" ); document.write( " 20 = 20
\n" ); document.write( "Checked!
\n" ); document.write( "Hope this helps :-)
\n" ); document.write( " \n" ); document.write( "
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