document.write( "Question 991158: 12 yrs ago I was one-third the age that I will be 8 years from now. how old am I today?\r
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\n" ); document.write( "\n" ); document.write( "let x= how old he is now.\r
\n" ); document.write( "\n" ); document.write( "x-12=1/3x+8
\n" ); document.write( "-1/3=-1/3
\n" ); document.write( "2/3x=20
\n" ); document.write( "*3/2x=20*3/2
\n" ); document.write( "x=30
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Algebra.Com's Answer #611148 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
i think you had the right idea, but you got lost in the math.
\n" ); document.write( "here's how it works.
\n" ); document.write( "x = your age now.
\n" ); document.write( "x - 12 = your age 12 years ago
\n" ); document.write( "x + 8 = your age 8 years from now.
\n" ); document.write( "12 years ago, you were 1/3 * the age that you will be 8 years from now.
\n" ); document.write( "the formula is:
\n" ); document.write( "x - 12 = 1/3 * (x + 8)
\n" ); document.write( "multiply both sides of this equation by 3 and you get:
\n" ); document.write( "3 * (x - 12) = 3 * 1/3 * (x + 8)
\n" ); document.write( "simplify to get:
\n" ); document.write( "3x - 36 = x + 8
\n" ); document.write( "subtract x from both sides of the equation and add 36 to both sides of the equation to get:
\n" ); document.write( "3x - x = x + 36
\n" ); document.write( "simplify to get:
\n" ); document.write( "2x = 44
\n" ); document.write( "divide both sides of the equation by 2 to get:
\n" ); document.write( "x = 22
\n" ); document.write( "you are 22 years of age today.
\n" ); document.write( "12 years ago you were 10.
\n" ); document.write( "8 years from now you will be 30.
\n" ); document.write( "10 is 1/3 * 30.
\n" ); document.write( "that's your solution.
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