document.write( "Question 1179481: A theater can seat 247 people. The number of rows is 6 less than the number of seats in each row. How many rows of seats are there?\r
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Algebra.Com's Answer #809061 by greenestamps(13200)\"\" \"About 
You can put this solution on YOUR website!


\n" ); document.write( "The standard algebraic solution shown by the other tutor uses x and x+6 for the two numbers whose difference is 6; that leads to a solution in which you need to factor the quadratic equation

\n" ); document.write( "\"x%5E2%2B6x-247=0\"

\n" ); document.write( "It will be difficult for most people to find that the correct factorization is

\n" ); document.write( "\"%28x%2B19%29%28x-13%29=0\"

\n" ); document.write( "leading to an answer of 13 rows of 19 seats each.

\n" ); document.write( "Here is a technique that can be used to make an algebraic solution easier in this and many similar problems.

\n" ); document.write( "Let the number of rows be x-3 and the number of seats in each row be x+3.

\n" ); document.write( "Note the difference of 6 between the two numbers was implemented by letting x be halfway between the two numbers.

\n" ); document.write( "Now the equation is solved much more easily:

\n" ); document.write( "\"%28x-3%29%28x%2B3%29=247\"
\n" ); document.write( "\"x%5E2-9=247\"
\n" ); document.write( "\"x%5E2=256\"
\n" ); document.write( "\"x=16\"

\n" ); document.write( "ANSWER: The number of rows is x-3=13

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