document.write( "Question 1145242: john is five years older than will. twice johns age in two years is same as four times will's age one year ago. how old is john now? \n" ); document.write( "

Algebra.Com's Answer #766470 by greenestamps(13200) $\"\"$ $\"About$

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\n" ); document.write( "There is nothing wrong with the solution shown by tutor @josgarithmetic. However, they made the problem much more work than necessary!

\n" ); document.write( "The obvious two equations from the given information are

\n" ); document.write( " $\"j+=+w%2B5\"$
\n" ); document.write( " $\"2%28j%2B2%29+=+4%28w-1%29\"$

\n" ); document.write( "Given two equations in that form, the easiest solution method is substitution.

\n" ); document.write( "But the other tutor went to the trouble of solving the second equation for j and substituting in the first equation, leading to a lot of calculations involving fractions.

\n" ); document.write( "It is rather silly to do that, when the first equation already gives you one variable in terms of the other!

\n" ); document.write( "So substitute what's given in the first equation into the second:

\n" ); document.write( " $\"2%28%28w%2B5%29%2B2%29+=+4%28w-1%29\"$
\n" ); document.write( " $\"2w%2B14+=+4w-4\"$
\n" ); document.write( " $\"18+=+2w\"$
\n" ); document.write( " $\"w+=+9\"$

\n" ); document.write( "So Will is 9; that makes John 9+5 = 14. \n" ); document.write( "

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