document.write( "Question 570833: Twice the sum of a number and 3 is 18. Find the number. \n" ); document.write( "
Algebra.Com's Answer #368577 by mathsmiles(68)\"\" \"About 
You can put this solution on YOUR website!
Let's take this one part at a time. \r
\n" ); document.write( "\n" ); document.write( "Let X be the number we're looking for.\r
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\n" ); document.write( "\n" ); document.write( "Take the sum of this number and 3:
\n" ); document.write( "X+3
\n" ); document.write( "Two times this:
\n" ); document.write( "2(X+3)
\n" ); document.write( "is 18\r
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\n" ); document.write( "\n" ); document.write( "So the equation is
\n" ); document.write( "2(X + 3) = 18
\n" ); document.write( "2X + 6 = 18\r
\n" ); document.write( "\n" ); document.write( "Subtract 6 from each side giving:
\n" ); document.write( "2X = 12\r
\n" ); document.write( "\n" ); document.write( "Divide both sides by 2 giving:
\n" ); document.write( "X = 6\r
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\n" ); document.write( "\n" ); document.write( "Checking:
\n" ); document.write( "The sum of 6 and 3 is 9
\n" ); document.write( "Twice that is 9 X 2 = 18 Correct!
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