document.write( "Question 166842: John owns a hotdog stand. He has found that his profit is represented by the equation P(x)= -x^2+62x+79, with P being profits and x the number of hotdogs sold. How many hotdogs must he sell to earn the most profit? \n" ); document.write( "

Algebra.Com's Answer #122913 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
To earn money, his profits have to be positive.
\n" ); document.write( " $\"P%28x%29%3E=0\"$
\n" ); document.write( "Let's find the point where the profits equal zero.
\n" ); document.write( "From that point on, his profit will be positive.
\n" ); document.write( " $\"P%28x%29=0\"$
\n" ); document.write( " $\"-x%5E2%2B62x%2B79=0\"$
\n" ); document.write( " $\"+graph%28+300%2C+300%2C+-10%2C+50%2C+-50%2C+1500%2C+-x%5E2%2B62x%2B79%29+\"$
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( ".
\n" ); document.write( "Check the equation.
\n" ); document.write( "John makes a $79 profit selling 0 hot dogs, that can't be right.
\n" ); document.write( "Also, when he sells more than a certain number (63), his profits become negative, that doesn't make sense either.
\n" ); document.write( "Check and re-post the problem.
\n" ); document.write( " \n" ); document.write( "

\n" );