document.write( "Question 818108: A rectangular auditorium seats 1505 people. The number of seats in each row exceeds the number of rows by 8. Find the number of seats in each row. \n" ); document.write( "
Algebra.Com's Answer #729123 by greenestamps(13198)\"\" \"About 
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\n" ); document.write( "I definitely concur with tutor ikleyn that this kind of problem is much better solved using a little logical reasoning, instead of formal mathematics. Indeed, when you try to solve it using the traditional algebraic approach, you end up having to factor a quadratic by finding two numbers whose product is 1505 and whose difference is 8. But THAT IS WHAT THE ORIGINAL PROBLEM asks you to do.

\n" ); document.write( "So the formal algebra is a waste of time....

\n" ); document.write( "And the \"trick\" tutor ikleyn uses is a very useful one. If you know that
\n" ); document.write( "\"x%28x-8%29=1505\"
\n" ); document.write( "then you know that
\n" ); document.write( "\"%28x%2B4%29%28x-4%29+=+1505%2B4%5E2+=+1505%2B16+=+1521+=+39%5E2\"
\n" ); document.write( "and so the answers are 39-4=35 and 39+4=43.

\n" ); document.write( "It did not occur to me to use that trick on this problem. I just started playing with numbers to find a pair with a product of 1505 and a difference of 8. There weren't many possibilities....

\n" ); document.write( "I of course first saw
\n" ); document.write( "\"1505+=+5%2A301\"

\n" ); document.write( "Then I had to find a factorization of 301; when I found it, I had my answer.

\n" ); document.write( "\"301+=+7%2A43\", so \"1505+=+5%2A7%2A43+=+35%2A43\".

\n" ); document.write( "Answer: 35 rows of 43 seats each.
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