document.write( "Question 73113: Can you please help me on this word problem...the profit on a watch is given by p=x^2-13x-80, where x is the number of watches sold per day. how many watches were sold on a day when there was a $50 loss. \n" ); document.write( "

Algebra.Com's Answer #52400 by Earlsdon(6294) $\"\"$ $\"About$

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The profit is:
\n" ); document.write( " $\"p+=+x%5E2-13x-80\"$
\n" ); document.write( "Find x when p = ($50.00) The parentheses indicate a loss so this really should be written as -$50.00.
\n" ); document.write( "So, you want to substitute p = -50 into the formula and solve for x, the number of watches.
\n" ); document.write( " $\"-50+=+x%5E2-13x-80\"$ Add 50 to both sides and write the quadratic equation in standard form.
\n" ); document.write( " $\"x%5E2-13x-30+=+0\"$ This can be factored.
\n" ); document.write( " $\"%28x%2B2%29%28x-15%29+=+0\"$ Apply the zero product principle.
\n" ); document.write( " $\"x%2B2+=+0\"$ and/or $\"x-15+=+0\"$
\n" ); document.write( " $\"x+=+-2\"$ Discard this solution as one cannot make a negative number of watches.
\n" ); document.write( " $\"x+=+15\"$ This is the solution.
\n" ); document.write( "15 watches were made on the day when there was a $50.00 loss. \n" ); document.write( "

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