document.write( "Question 417894: An orchard contains 30 apple trees, each of which yields approximately 400 apples over the growing season.
\n" ); document.write( "The owner plans to add more trees, but the guys at Texas A&M advise that because of crowding, each new tree will reduce the average yield per tree by about 10 apples over the growing season.
\n" ); document.write( "How many trees should be added to maximize the total yield of apples, and what is the maximum yield?
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Algebra.Com's Answer #292519 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"x\" = number of trees to be added
\n" ); document.write( "Let \"Y\" = yield from orchard
\n" ); document.write( "\"Y+=+400%2A%2830+%2B+x%29+-+10x%2A%28+30+%2B+x%29+\"
\n" ); document.write( "\"Y+=+%28400+-+10x%29%2A%2830+%2B+x%29+\"
\n" ); document.write( "\"+Y+=+12000+-+300x+%2B+400x+-+10x%5E2+\"
\n" ); document.write( "\"Y+=+-10x%5E2+%2B+100x+%2B+12000\"
\n" ); document.write( "The maximum of a quadratic is at \"+-b%2F%282a%29+\"
\n" ); document.write( "\"-b%2F%282a%29+=+-100%2F%28-20%29+\"
\n" ); document.write( "\"-100%2F%28-20%29+=+5\"
\n" ); document.write( "5 trees should be added to maximize yield
\n" ); document.write( "The yield, \"Y\", is
\n" ); document.write( "\"Y+=+-10%2A5%5E2+%2B+100%2A5+%2B+12000\"
\n" ); document.write( "\"Y+=+-250+%2B+500+%2B+12000\"
\n" ); document.write( "\"Y+=+12250\"
\n" ); document.write( "Here's a plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-20%2C+60%2C+-1000%2C+15000%2C+-10x%5E2+%2B+100x+%2B+12000%29+\"
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