document.write( "Question 82514: A two-digit counting number has a value that is 7 times the sum of its digits. If 5 times the units' digit is 9 more than the tens' digit, what is the number. \n" ); document.write( "
Algebra.Com's Answer #59111 by ankor@dixie-net.com(22740)\"\" \"About 
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Let x = the 10's digit; let y = the units digt
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\n" ); document.write( "A two-digit counting number has a value that is 7 times the sum of its digits.
\n" ); document.write( " 10x + y = 7(x + y)
\n" ); document.write( " 10x + y = 7x + 7y
\n" ); document.write( " 10x - 7x = 7y - y
\n" ); document.write( " 3x = 6y
\n" ); document.write( " x = 2y: divided both sides by 3
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\n" ); document.write( " If 5 times the units' digit is 9 more than the tens' digit, what is the number.
\n" ); document.write( " 5y = x + 9
\n" ); document.write( "Substitute 2y for x and find y
\n" ); document.write( " 5y = 2y + 9
\n" ); document.write( " 5y - 2y = 9
\n" ); document.write( " 3y = 9
\n" ); document.write( " y = 9/3
\n" ); document.write( " y = 3 is the units digit
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\n" ); document.write( "Find x:
\n" ); document.write( "x = 2y
\n" ); document.write( "x = 2(3)
\n" ); document.write( "x = 6
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\n" ); document.write( "The two digit number is 63
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\n" ); document.write( "Check: Does the number = 7 times the sum of the digits?
\n" ); document.write( " 63 = 7(6+3), yes it does \n" ); document.write( "
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