A city manager made a scatter plot of the number of retail stores in a certain city over the years. The scatter plot h ad a trend line with an equation of y =11x +12, where y is the total number of retail stores and x is the number of years since 1990. 9. Tracy and her family moved to the city in 2003. Use the equation to predict how many retail stores there were in 2003.

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

is the anwser b. (-13)?

is this the complete