B
Round your answer to the nearest hundredth.
A
9
B
5

  56.25°

Step-by-step explanation:

The definition of the cosine function tells you that

  cos(B) = BC/BA

  B = arccos(BC/BA) = arccos(5/9)

  B ≈ 56.25°

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