document.write( "Question 382537: The sum of two numbers is 135. The difference between them is 9. Find the numbers. \n" ); document.write( "

Algebra.Com's Answer #271063 by nerdybill(7384) $\"\"$ $\"About$

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The sum of two numbers is 135. The difference between them is 9. Find the numbers.
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\n" ); document.write( "Let x = first number
\n" ); document.write( "and y = second number
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\n" ); document.write( "from: \"The sum of two numbers is 135\" we get
\n" ); document.write( "x + y = 135 (equation 1)
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\n" ); document.write( "from: \"The difference between them is 9\" we get
\n" ); document.write( "x - y = 9 (equation 2)
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\n" ); document.write( "Solve equation 2 for y:
\n" ); document.write( "x - y = 9
\n" ); document.write( "x - 9 = y
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\n" ); document.write( "Substitute the above into equation 1 and solve for x:
\n" ); document.write( "x + y = 135
\n" ); document.write( "x + x - 9 = 135
\n" ); document.write( "2x - 9 = 135
\n" ); document.write( "2x = 144
\n" ); document.write( "x = 72
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\n" ); document.write( "Substitute above into equation 2 and solve for y:
\n" ); document.write( "x - y = 9
\n" ); document.write( "72 - y = 9
\n" ); document.write( "-y = -63
\n" ); document.write( "y = 63
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\n" ); document.write( "Answer: 63 and 72 \n" ); document.write( "

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