document.write( "Question 481455: a two digit number is 4 times the sum of its digits, if the number is doubled and then decreased by 12, the result is the number with the digits reversed. what is the number? \n" ); document.write( "
Algebra.Com's Answer #329702 by ankor@dixie-net.com(22740)\"\" \"About 
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Let x = the 10's digit, Let y = units
\n" ); document.write( "then
\n" ); document.write( "10x+y is the two digit number
\n" ); document.write( "and
\n" ); document.write( "10y+x is the number reversed
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each statement:
\n" ); document.write( ":
\n" ); document.write( "\"two digit number is 4 times the sum of its digits,\"
\n" ); document.write( "10x + y = 4(x+y)
\n" ); document.write( "10x + y = 4x + 4y
\n" ); document.write( "10x - 4x = 4y - y
\n" ); document.write( "6x = 3y
\n" ); document.write( "Simplify, divide both sides by 2
\n" ); document.write( "2x = y
\n" ); document.write( ":
\n" ); document.write( "\"if the number is doubled and then decreased by 12, the result is the number with the digits reversed.
\n" ); document.write( "2(10x+y) - 12 = 10y + x
\n" ); document.write( "20x + 2y - 12 = 10y + x
\n" ); document.write( "20x - x = 10y - 2y + 12
\n" ); document.write( "19x = 8y + 12
\n" ); document.write( "Replace y with 2x (from the 1st equation)
\n" ); document.write( "19x = 8(2x) + 12
\n" ); document.write( "19x = 16x + 12
\n" ); document.write( "19x - 16x = 12
\n" ); document.write( "3x = 12
\n" ); document.write( "x = 4 is the 10's digit
\n" ); document.write( "and
\n" ); document.write( "y = 2(4)
\n" ); document.write( "y = 8 is the units
\n" ); document.write( "therefore
\n" ); document.write( "48 is the number
\n" ); document.write( ":
\n" ); document.write( "You can confirm this by using 48 as the number in both statements \n" ); document.write( "
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