document.write( "Question 50513: Hi, the following question I dont know where to start with:
\n" ); document.write( "it is the daily profit for whitegoods store from sale of bar fridges is given by P(x)= -x^2+40x+825 where x is number of bar fridges sold. Find the function's vertex and intercepts.
\n" ); document.write( "Thanks very much if you could please help me with this one! \n" ); document.write( "
Algebra.Com's Answer #33595 by Nate(3500)\"\" \"About 
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P(x) = -x^2 + 40x + 825
\n" ); document.write( "v(-b/2a,f(x))
\n" ); document.write( "-b/2a = -40/(2*-1) = -40/-2 = 20
\n" ); document.write( "P(20) = -(20)^2 + 40(20) + 825 = -400 + 800 + 825 = 1,225
\n" ); document.write( "v(20,1225)
\n" ); document.write( "x-intercepts
\n" ); document.write( "0 = -x^2 + 40x + 825
\n" ); document.write( "825 = x^2 - 40x
\n" ); document.write( "825 + 400 = (x - 20)^2
\n" ); document.write( "1225 = (x - 20)^2
\n" ); document.write( "+-35 = x - 20
\n" ); document.write( "20+-35 = x
\n" ); document.write( "(-15,0) and (55,0) are the intercepts
\n" ); document.write( "\"graph%28600%2C600%2C-16%2C56%2C-20%2C1226%2C-x%5E2%2B40x%2B825%29\" \n" ); document.write( "
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