Select the points that are solutions to the system of inequalities. Select all that apply.
A. (1,2)
B. (-10,10)
C. (-2,0)
D. (0,10)

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

answer is  

c.

56

hope you get this right