document.write( "Question 590352: How do I solve 2x+3y=18 and x=2y-5 its one problem and I want to use the substitution method.thanks \n" ); document.write( "
Algebra.Com's Answer #375120 by Theo(13342)\"\" \"About 
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2x + 3y = 18
\n" ); document.write( "x = 2y-5
\n" ); document.write( "substitute 2y-5 for x in the first equation to get:
\n" ); document.write( "2(2y-5) + 3y = 18
\n" ); document.write( "simplify by removing parentheses to get:
\n" ); document.write( "4y - 10 + 3y = 18
\n" ); document.write( "combine like terms to get:
\n" ); document.write( "7y - 10 = 18
\n" ); document.write( "add 10 to both sides to get:
\n" ); document.write( "7y = 28
\n" ); document.write( "divide both sides by 7 to get:
\n" ); document.write( "y = 4
\n" ); document.write( "substitute 4 for y in the second equation of x = 2y-5 to get:
\n" ); document.write( "x = 2*4-5 which becomes:
\n" ); document.write( "x = 8-5 which becomes:
\n" ); document.write( "x = 3
\n" ); document.write( "substitute 3 for x and 4 for y in the first equation of 2x + 3y = 18 to get:
\n" ); document.write( "2*3 + 3*4 = 18 which becomes:
\n" ); document.write( "6 + 12 = 18 which becomes:
\n" ); document.write( "18 = 18
\n" ); document.write( "values for x and y are good.
\n" ); document.write( "x = 3
\n" ); document.write( "y = 4
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