document.write( "Question 242805: One number is eleven more than twice another. If their sum is decreased by nine, the result is seventeen. Find the numbers \n" ); document.write( "
Algebra.Com's Answer #177776 by oberobic(2304)\"\" \"About 
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In the setup to the problem, always try to minimize the unknowns.
\n" ); document.write( "x = one number
\n" ); document.write( "It is 11 more than twice another number.
\n" ); document.write( "y = another number
\n" ); document.write( "x = 2y + 11
\n" ); document.write( "...
\n" ); document.write( "Now the second part says if the sum of x + y is decreased by 9 (that is: x + y - 9), the result is 17.
\n" ); document.write( "x + y - 9 = 17
\n" ); document.write( "Add 9 to both sides
\n" ); document.write( "x + y = 17+9 = 26
\n" ); document.write( "...
\n" ); document.write( "Now we have to solve x and y
\n" ); document.write( "...
\n" ); document.write( "Subtracting y from both sides of the equation above.
\n" ); document.write( "x + y - y = 26 - y
\n" ); document.write( "x = 26 - y
\n" ); document.write( "...
\n" ); document.write( "Substituting in the other equation.
\n" ); document.write( "x = 2y + 11
\n" ); document.write( "26 - y = 2y + 11
\n" ); document.write( "Adding y to both sides
\n" ); document.write( "26 = 3y + 11
\n" ); document.write( "Subtracting 11 from both sides
\n" ); document.write( "15 = 3y
\n" ); document.write( "Dividing both sides by 3
\n" ); document.write( "5 = y
\n" ); document.write( "...
\n" ); document.write( "y = 5
\n" ); document.write( "...
\n" ); document.write( "Recall
\n" ); document.write( "x + y = 26
\n" ); document.write( "Substituting for y
\n" ); document.write( "x + 5 = 26
\n" ); document.write( "Subtracting 5 from both sides
\n" ); document.write( "x = 21
\n" ); document.write( "Check your work (even if you're tired)...
\n" ); document.write( "Does x = 2y + 11?
\n" ); document.write( "21 = 2(5) + 11?
\n" ); document.write( "Yes it does.
\n" ); document.write( "Does x + y - 9 = 17?
\n" ); document.write( "21 + 5 - 9 = 17?
\n" ); document.write( "Yes it does.
\n" ); document.write( "So we're done.
\n" ); document.write( "x = 21
\n" ); document.write( "y = 5
\n" ); document.write( "
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