Seth wants to create a replica of a doughnut for a rooftop sign for his bakery. The replica has a diameter of 18 feet. The diameter of the hole in the center is equal to the replica's radius. Once the replica is built, Seth wants to string small lights around the outer edge. How long will the string of lights need to be?

A. Write a numerical expression for the length of the string of lights needed.

B. Simplify your expression. Use 3.14 as an approximation for .

C. Explain how you got your answer.

x equals 1

step-by-step explanation:

f(4)=f(×)

x=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

answer: yes, since the line has a steeper rate of change than the exponential the y-values will be greater and they will only intersect one time.