document.write( "Question 440163: The number of fruit flies F(x) in a farming area depends on the spring rainfall x: F(x) = 15x – x^2. What rainfall produces the maximum number of fruit flies?
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Algebra.Com's Answer #304127 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "The number of fruit flies F(x) in a farming area depends on the spring rainfall x: 
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document.write( " f(x) = -x^2+15x  |graphically a parabola opening downward a< 0
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document.write( "Using the vertex form of a parabola,  where(h,k) is the vertex
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document.write( " f(x) = -(x -7.5)^2 + 56.25     | completing the square to find the vertex
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document.write( " Vertex is Pt(7.5, 56.25)
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document.write( "     7.5\" rainfall produces the maximum number of fruit flies 
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