document.write( "Question 64575: To solve systems of equations by the substitution method. Please help my son to solve this homework questions:\r
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document.write( "x – y = 3
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document.write( "6x + 4y = 13
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Algebra.Com's Answer #45205 by 303795(602)![]() ![]() ![]() You can put this solution on YOUR website! In the substitution method one equation is written with one variable on its own on one side of the equation. \n" ); document.write( "Rewrite the first equation by adding y to each side of the equation to get \n" ); document.write( "x – y + y = 3 + y \n" ); document.write( "x = y + 3 \n" ); document.write( "Substitute for x in the second equation. \n" ); document.write( "6(y + 3) + 4y = 13 \n" ); document.write( "6y + 18 + 4y = 13 \n" ); document.write( "10y + 18 = 13 \n" ); document.write( "Subtract 18 from each side of the equation \n" ); document.write( "10y + 18 - 18 = 13 - 18 \n" ); document.write( "10y = -5 \n" ); document.write( "Divide each side by 10 \n" ); document.write( "y = -0.5 \n" ); document.write( "Substitute into the first equation (or its modified form) \n" ); document.write( "x = y + 3 \n" ); document.write( "x = -0.5 + 3 \n" ); document.write( "x = 2.5 \n" ); document.write( " |