document.write( "Question 993532: How do you solve 4x+5y=25 and 8x-5y=35 when using substitution
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Algebra.Com's Answer #612792 by ikleyn(52797)\"\" \"About 
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\n" ); document.write( "How do you solve  4x+5y=25  and  8x-5y=35 when using substitution.
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\n" ); document.write( "\n" ); document.write( "\"system%284x%2B5y=25%2C%0D%0A8x-5y=35%29\".\r
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\n" ); document.write( "\n" ); document.write( "You can express  4x  from the first equation,  4x = 25-5y,  and then substitute it into the second equation.  You will get\r
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\n" ); document.write( "\n" ); document.write( "2*(25-5y) - 5y = 35.\r
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\n" ); document.write( "\n" ); document.write( "Simplify and solve:\r
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\n" ); document.write( "\n" ); document.write( "50 - 10y - 5y = 35,\r
\n" ); document.write( "\n" ); document.write( "15y = 30 - 35,\r
\n" ); document.write( "\n" ); document.write( "15y = 15, \r
\n" ); document.write( "\n" ); document.write( "y = 1.\r
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\n" ); document.write( "\n" ); document.write( "Now substitute the found value of  y=1  into the first equation to find  x.  You will get \r
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\n" ); document.write( "\n" ); document.write( "4x + 5*1 = 25,\r
\n" ); document.write( "\n" ); document.write( "4x = 20, \r
\n" ); document.write( "\n" ); document.write( "x = 5.\r
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\n" ); document.write( "\n" ); document.write( "Answer.  x = 5, y = 1.\r
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