document.write( "Question 765848: John owns a hot dog stand. He has found that his profit is represented by the equation P = -x2 + 56x + 77, with
\n" ); document.write( "P being profit in dollars and x the number of hot dogs. Using this model, what is the maximum profit that John
\n" ); document.write( "can make? How many hot dogs must he sell in order to to obtain that maximum profit?\r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #466451 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "\"P+=+-x%5E2+%2B+56x+%2B+77\"........this is a parabola; since the coefficient of leading term is \"-1\", parabola turns downward and the vertex will be maximum\r
\n" ); document.write( "\n" ); document.write( "so, we need to find the coordinates (\"h\",\"k\") of a vertex\r
\n" ); document.write( "\n" ); document.write( "use the formula \"h+=+-b%2F2a\" to find the \"x\" coordinate \"h\" of the vertex of a parabola and \"k+=+P%28h%29\" to find the \"y\" coordinate \"k\" of the vertex\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"h+=+-56%2F2%28-1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"h+=+-56%2F-2\"\r
\n" ); document.write( "\n" ); document.write( "\"h+=+28\"...........since \"h+=+x\", this is the number of hot dogs\r
\n" ); document.write( "\n" ); document.write( "\"P%2828%29+=+-28%5E2+%2B+56%2A28+%2B+77\"\r
\n" ); document.write( "\n" ); document.write( "\"P%2828%29+=-784+%2B+1568+%2B+77\"\r
\n" ); document.write( "\n" ); document.write( "\"P%2828%29+=861\"..........since \"k+=+y\", this is maximum profit\r
\n" ); document.write( "\n" ); document.write( "so, the vertex is at (\"h\",\"k\")=(\"28\",\"861\")\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );