document.write( "Question 1203125: Brooklyn has a summer window washing business. Based on experience Brooklyn knows that P= - 2x² + 130x - 1500 models her profit, P, in dollars, where x is the amount she charges per window. How much must Brooklyn charge to maximize her profit? What is the maximum profit?\r
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Algebra.Com's Answer #838435 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Brooklyn has a summer window washing business. Based on experience
\n" ); document.write( "Brooklyn knows that P= - 2x² + 130x - 1500 models her profit, P, in dollars,
\n" ); document.write( "where x is the amount she charges per window.
\n" ); document.write( "(a) How much must Brooklyn charge to maximize her profit?
\n" ); document.write( "(b) What is the maximum profit?
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document.write( "They want you find the maximum of the quadratic function P(x) = -2x^2 + 130x - 1500.\r\n" );
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document.write( "It is well known fact that a quadratic function f(x) = ax^2 + bx + c gets its maximum value at  \r\n" );
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document.write( "               = .\r\n" );
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document.write( "In your case,  a= -2, b= 130,  therefore,   =  =  = 32.50 dollars.\r\n" );
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document.write( "The maximum profit is then  P(32.50) = -2*32.50^2 + 130*32.50 - 1500 = 612.50 dollars.\r\n" );
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document.write( "ANSWER.  (a) $32.50;  (b) $612.50.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On finding the maximum/minimum of a quadratic function see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the vertex of a parabola\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the vertex of a parabola\r
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.\r
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