Which of these statements is true for f(x) = (9/10)X? O A. It is always decreasing.
B. The domain of f(x) is x > 0
C. The range of f(x) is y > 9/10
D. The y-intercept is (0,1)

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204