document.write( "Question 1028708: The Diver Time Company makes digital watches for scuba divers. The company models its profits with the function P(d)=-2d^2 + 13d- 6, where d is the number of watches sold in hundreds, and P(d) is the company's profit, in tens of thousands of dollars.
\n" ); document.write( "a) how many watches must the company sell in order to break even? show your work.
\n" ); document.write( "b)How many watches does Diver Time need to sell to maximize profits? Explain
\n" ); document.write( "c) What is the maximum profit? Explain.\r
\n" ); document.write( "\n" ); document.write( "Thanks :)))
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Algebra.Com's Answer #643792 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
\"+P%28d%29+=+-2d%5E2+%2B+13d+-+6+\"
\n" ); document.write( "The break even point is where \"+P%28d%29+=+0+\",
\n" ); document.write( "or no profit
\n" ); document.write( "(a)
\n" ); document.write( "\"+-2d%5E2+%2B+13d+-+6+=+0+\"
\n" ); document.write( "Use quadratic formula
\n" ); document.write( "\"+d+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"
\n" ); document.write( "\"+a+=+-2+\"
\n" ); document.write( "\"+b+=+13+\"
\n" ); document.write( "\"+c+=+-6+\"
\n" ); document.write( "\"+d+=+%28-13+%2B-+sqrt%28+13%5E2+-+4%2A%28-2%29%2A%28-6%29+%29%29+%2F+%282%2A%28-2%29%29+\"
\n" ); document.write( "\"+d+=+%28-13+%2B-+sqrt%28+169+-+48+%29%29+%2F%28-4+%29\"
\n" ); document.write( "\"+d+=+%28-13+%2B-+sqrt%28+121+%29%29+%2F%28-4+%29\"
\n" ); document.write( "\"+d+=+%28-13+%2B+11%29+%2F%28-4+%29\"
\n" ); document.write( "\"+d+=+%28-2%29+%2F+%28-4%29+\"
\n" ); document.write( "\"+d+=+.5+\" hundreds
\n" ); document.write( "and
\n" ); document.write( "\"+d+=+%28+-13+-+11+%29+%2F+%28-4%29+\"
\n" ); document.write( "\"+d+=+%28-24%29+%2F+%28-4%29+\"
\n" ); document.write( "\"+d+=+6+\" hundreds
\n" ); document.write( "There are 2 break even points:
\n" ); document.write( "50 watches sold and
\n" ); document.write( "600 watches sold
\n" ); document.write( "----------------
\n" ); document.write( "(b)
\n" ); document.write( "The maximum profit is where:
\n" ); document.write( "\"+p+=+-b%2F%282a%29+\"
\n" ); document.write( "\"+p+=+-13%2F%28+2%2A%28-2%29%29+\"
\n" ); document.write( "\"+p+=+%28-13%29%2F%28-4%29+\"
\n" ); document.write( "\"+p+=+13%2F4+\"
\n" ); document.write( "\"+%2813%2F4%29%2A100+=+325+\"
\n" ); document.write( "When 325 watches are sold, the profit is maximum
\n" ); document.write( "----------------
\n" ); document.write( "check:
\n" ); document.write( "here's the plot:
\n" ); document.write( "\"+graph%28+500%2C+500%2C+-2%2C10%2C+-10%2C+16%2C+-2x%5E2+%2B+13x+-+6+%29+\"
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