document.write( "Question 1184033: the sum of three numbers is 15. The second number is two less than the first number. The sum of the first two numbers is twice the third number. Identify the three numbers. \n" ); document.write( "
Algebra.Com's Answer #814566 by ankor@dixie-net.com(22740)\"\" \"About 
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Sum of three numbers is 15.
\n" ); document.write( " a + b + c = 15
\n" ); document.write( "The second number is two less than the first number.
\n" ); document.write( " b = a - 2
\n" ); document.write( "or we can rearrange and write it
\n" ); document.write( "a - b = 2
\n" ); document.write( "The sum of the first two numbers is twice the third number.
\n" ); document.write( " a + b = 2c\r
\n" ); document.write( "\n" ); document.write( "Identify the three numbers.
\n" ); document.write( ":
\n" ); document.write( "Notice a + b is in 1st and 3rd equation, so in the 1st equation we can write it
\n" ); document.write( "2c + c = 15
\n" ); document.write( "3c = 15
\n" ); document.write( "c = 15/3
\n" ); document.write( "c = 5
\n" ); document.write( "In the 1st equation, replace c with 5
\n" ); document.write( "a + b + 5 = 15
\n" ); document.write( "a + b = 15 - 5
\n" ); document.write( "a + b = 10
\n" ); document.write( "Use elimination with rearranged equation
\n" ); document.write( "a + b = 10
\n" ); document.write( "a - b = 2
\n" ); document.write( "-----------addition eliminates b, find a
\n" ); document.write( "2a + 0 = 12
\n" ); document.write( "a = 12/2
\n" ); document.write( "a = 6
\n" ); document.write( "find b
\n" ); document.write( "6 + b = 10
\n" ); document.write( "b = 10 - 6
\n" ); document.write( "b = 4
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check: 6 + 4 + 5 = 15 \n" ); document.write( "
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